Gong OAuth refresh token invalid_grant — What it means & how to fix it

Integrating with Gong via OAuth 2.0 requires managing single-use refresh tokens, which can lead to failures such as "invalid_grant" if not handled correctly, causing sync jobs to stop and dashboards to become outdated. These issues often stem from concurrency problems, where multiple workers try to refresh the token simultaneously, or from using incorrect OAuth credentials. To address these failures, it's crucial to persist the newest refresh token after every successful refresh, ensure only one refresh request per connection is in flight, and verify the use of Gong's documented OAuth endpoints. If issues persist, reauthorization may be necessary. To prevent such problems, developers should always assume refresh tokens rotate on every refresh, employ single-flight refreshes, and maintain clear user interfaces for reconnecting to Gong. Nango, an open-source API authentication tool, offers solutions like automated token refreshing and rotation, which can simplify the integration process by handling the token lifecycle, allowing developers to focus on product features.