kin_kon | Stripe Developers | Page 1

The metadata, is it on the Checkout Session object?

You probably want to set it on the Subscription level instead https://stripe.com/docs/api/checkout/sessions/create#create_checkout_session-subscription_data-metadata

Create a Session | Stripe API Reference

Complete reference documentation for the Stripe API. Includes code snippets and examples for our Python, Java, PHP, Node.js, Go, Ruby, and .NET libraries.

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