# Page Not Found

The URL `admin-apis/subscription-management/changing-the-subscriptions-external-reference-identifier` does not exist.

You might be looking for one of these pages:
- [Changing the subscription's external reference identifier](https://docs.digitalriver.com/commerce-api/admin-apis/subscription-management/immediately-change-the-subscription/changing-the-subscriptions-external-reference-identifier.md)
- [Update the subscription at the next renewal](https://docs.digitalriver.com/commerce-api/admin-apis/subscription-management/update-the-subscription-at-the-next-renewal.md)
- [Getting a subscription by identifier](https://docs.digitalriver.com/commerce-api/admin-apis/subscription-management/retrieve-the-subscription/getting-a-subscription-by-identifier.md)
- [Subscription notifications](https://docs.digitalriver.com/commerce-api/admin-apis/subscription-management/subscription-notifications.md)
- [Using the Expired Card Optimizer](https://docs.digitalriver.com/commerce-api/admin-apis/subscription-management/using-the-expired-card-optimizer.md)

## How to find the correct page

1. **Browse the full index**: [/sitemap.md](https://docs.digitalriver.com/commerce-api/sitemap.md) - Complete documentation index
2. **View the full content**: [/llms-full.txt](https://docs.digitalriver.com/commerce-api/llms-full.txt) - Full content export

## Tips for requesting documentation

- For markdown responses, append `.md` to URLs (e.g., `/commerce-api/admin-apis/subscription-management/immediately-change-the-subscription/changing-the-subscriptions-external-reference-identifier.md`)
- Use `Accept: text/markdown` header for content negotiation