> ## Documentation Index > Fetch the complete documentation index at: https://developers.appstle.com/llms.txt > Use this file to discover all available pages before exploring further. # Send payment method update email to customer > Triggers Shopify to send an email to the subscription customer with a secure link to update their payment method. This endpoint initiates Shopify's native payment update flow without requiring direct payment handling. **Key Features:** - Sends official Shopify payment update email to customer - Customer receives secure link to Shopify-hosted payment update page - No PCI compliance required - Shopify handles all payment data - Supports all Shopify-supported payment methods - Automatically updates subscription after customer completes the process **Process Flow:** 1. API call triggers email send request to Shopify 2. Shopify sends branded email to customer's registered email 3. Customer clicks secure link in email 4. Customer authenticates on Shopify-hosted page 5. Customer adds/updates payment method 6. Subscription automatically uses new payment method **Email Details:** - Sent from Shopify's email servers - Uses store's configured sender email - Subject line typically: "Update your payment method" - Contains secure, time-limited link - Shopify-branded with store information **Use Cases:** - Failed payment recovery - Expiring credit card updates - Customer-requested payment changes - Proactive payment method maintenance **Important Notes:** - Customer must have valid email address - Email cannot be customized (Shopify template) - Link expiration time set by Shopify - Multiple emails can be sent if needed - No webhook for completion - poll contract for updates **Rate Limiting:** - Subject to Shopify's email sending limits - Recommended: Wait 24 hours between sends to same customer - Excessive sends may be blocked by Shopify **Authentication:** Requires valid X-API-Key header ## OpenAPI ````yaml /subscription/admin-api-swagger.json put /api/external/v2/subscription-contracts-update-payment-method openapi: 3.0.1 info: description: >- Comprehensive API documentation for managing subscriptions, payments, and related operations. These APIs allow you to programmatically manage subscription lifecycles, handle payments, configure products, and integrate subscription functionality into your applications. title: Admin APIs version: 0.0.1 servers: - url: https://subscription-admin.appstle.com security: [] tags: - description: >- Core APIs for managing the complete subscription lifecycle including creation, updates, pausing, resuming, and cancellation of subscriptions. name: Subscription Management - description: >- APIs for managing subscription payment methods, processing payments, handling payment retries, and updating billing information. name: Subscription Payments - description: >- APIs for managing subscription contracts including delivery schedules, pricing, order notes, billing cycles, and shipping addresses. name: Subscription Contracts - description: >- APIs for managing products within subscriptions including adding, removing, updating quantities, and swapping products. name: Subscription Products - description: >- APIs for handling billing operations, payment processing, and financial transactions related to subscriptions. name: Billing & Payments - description: >- APIs for managing discounts and promotional codes applied to subscriptions. name: Subscription Discounts - description: >- APIs for managing one-time add-on products that can be purchased alongside recurring subscription items. name: Subscription One-Time Products - description: >- APIs for managing subscription plans, pricing tiers, and plan configurations. name: Subscription Plans - description: >- APIs for managing customizable product boxes and bundles where customers can select multiple items. name: Build-a-Box & Bundles - description: >- APIs for managing the product catalog including product information, variants, and inventory. name: Product Catalog - description: >- APIs for managing operational settings, configurations, and administrative functions. name: Operations & Settings - description: >- APIs powering the customer-facing portal where subscribers can manage their own subscriptions. name: Customer Portal - description: APIs for managing customer information, profiles, and account details. name: Customers - description: >- APIs for retrieving aggregated subscription data, customer subscription history, and account-level subscription information. name: Subscription Data - description: >- APIs for managing delivery profiles, shipping rates, free shipping configuration, and delivery method options on subscriptions. name: Delivery & Shipping - description: >- APIs for managing storefront customization including custom CSS, theme settings, label translations, and merchant-defined widget configuration. name: Customization - description: >- APIs for configuring cancellation flows, retention offers, cancellation reason management, and win-back automation. name: Customer Retention paths: /api/external/v2/subscription-contracts-update-payment-method: put: tags: - Subscription Payments - Subscription Contracts summary: Send payment method update email to customer description: >- Triggers Shopify to send an email to the subscription customer with a secure link to update their payment method. This endpoint initiates Shopify's native payment update flow without requiring direct payment handling. **Key Features:** - Sends official Shopify payment update email to customer - Customer receives secure link to Shopify-hosted payment update page - No PCI compliance required - Shopify handles all payment data - Supports all Shopify-supported payment methods - Automatically updates subscription after customer completes the process **Process Flow:** 1. API call triggers email send request to Shopify 2. Shopify sends branded email to customer's registered email 3. Customer clicks secure link in email 4. Customer authenticates on Shopify-hosted page 5. Customer adds/updates payment method 6. Subscription automatically uses new payment method **Email Details:** - Sent from Shopify's email servers - Uses store's configured sender email - Subject line typically: "Update your payment method" - Contains secure, time-limited link - Shopify-branded with store information **Use Cases:** - Failed payment recovery - Expiring credit card updates - Customer-requested payment changes - Proactive payment method maintenance **Important Notes:** - Customer must have valid email address - Email cannot be customized (Shopify template) - Link expiration time set by Shopify - Multiple emails can be sent if needed - No webhook for completion - poll contract for updates **Rate Limiting:** - Subject to Shopify's email sending limits - Recommended: Wait 24 hours between sends to same customer - Excessive sends may be blocked by Shopify **Authentication:** Requires valid X-API-Key header operationId: updatePaymentMethodV2 parameters: - description: >- Subscription contract ID for payment method update. Must be a valid contract ID that belongs to the authenticated shop. example: 123456789 in: query name: contractId required: true schema: format: int64 minimum: 1 type: integer - deprecated: true description: API Key (Deprecated - Use X-API-Key header instead) in: query name: api_key required: false schema: type: string - description: API Key for authentication in: header name: X-API-Key required: true schema: type: string responses: '200': content: application/json: example: message: Payment method update email sent successfully description: Payment update email sent successfully '400': content: application/json: examples: Cancelled Subscription: description: Cancelled Subscription value: detail: >- Payment method cannot be updated for cancelled subscriptions instance: >- /api/external/v2/subscription-contracts-update-payment-method status: 400 title: UserGeneratedError:Cannot update cancelled subscription type: https://example.com/errors/bad-request Contract Not Found: description: Contract Not Found value: detail: 'No subscription contract found with ID: 123456789' instance: >- /api/external/v2/subscription-contracts-update-payment-method status: 400 title: Contract not found type: https://example.com/errors/bad-request Customer Not Found: description: Customer Not Found value: detail: Customer associated with payment method not found instance: >- /api/external/v2/subscription-contracts-update-payment-method status: 400 title: UserGeneratedError:Customer not found type: https://example.com/errors/bad-request Email Service Error: description: Email Service Error value: detail: Shopify email service temporarily unavailable instance: >- /api/external/v2/subscription-contracts-update-payment-method status: 400 title: UserGeneratedError:Email could not be sent type: https://example.com/errors/bad-request Invalid Email Address: description: Invalid Email Address value: detail: Cannot send email to invalid email address instance: >- /api/external/v2/subscription-contracts-update-payment-method status: 400 title: UserGeneratedError:Customer email is invalid type: https://example.com/errors/bad-request No Payment Method: description: No Payment Method value: detail: Subscription has no associated payment method instance: >- /api/external/v2/subscription-contracts-update-payment-method status: 400 title: Payment method not found type: https://example.com/errors/bad-request description: Invalid request or email send failed '401': content: application/json: example: detail: Valid X-API-Key header is required instance: /api/external/v2/subscription-contracts-update-payment-method status: 401 title: Authentication required type: https://example.com/errors/unauthorized description: Authentication required '403': content: application/json: example: detail: API key does not have permission to update payment methods instance: /api/external/v2/subscription-contracts-update-payment-method status: 403 title: Insufficient permissions type: https://example.com/errors/forbidden description: Insufficient permissions '404': description: Subscription contract not found '422': content: application/json: examples: Rate Limit Exceeded: description: Rate Limit Exceeded value: detail: >- Payment update email was recently sent. Please wait before sending another. instance: >- /api/external/v2/subscription-contracts-update-payment-method status: 422 title: UserGeneratedError:Too many emails sent type: https://example.com/errors/unprocessable-entity Shopify API Error: description: Shopify API Error value: detail: Unable to send payment update email at this time instance: >- /api/external/v2/subscription-contracts-update-payment-method status: 422 title: Shopify API error type: https://example.com/errors/unprocessable-entity description: Email cannot be sent due to business rules ````