Softphone fails to initialize for migrated Zendesk agents with 401 Unauthorized

Hey everyone, I’ve run into a really strange issue with the Genesys Cloud softphone initialization during our Zendesk-to-GC migration. In Zendesk Talk, agents just clicked ‘call’ and it worked via the plugin. Here, the softphone icon stays grayed out, and the browser console throws a 401 Unauthorized error when hitting the /api/v2/users/me/telephony/users endpoint. The agents are authenticated in the UI, so the token seems valid, but the telephony service rejects the handshake. This feels like a permissions sync issue similar to how Zendesk API tokens sometimes lag behind user role updates.

  • Verified that the agents have the Telephony capability enabled in their User Profiles, matching the Zendesk Agent role permissions.
  • Cleared cache and tested in incognito mode to rule out stale session tokens, but the 401 persists.

Is there a specific delay or manual step required to activate telephony permissions after migrating user data from Zendesk? The migration script ran successfully, but the telephony endpoints seem to be checking a different attribute.

This looks like a token scope mismatch rather than a full authentication failure. The UI session token often lacks the telephony:access scope required for the softphone handshake.

Verify the OAuth client configuration used during the Zendesk integration. Ensure the telephony scope is explicitly enabled for the connected app, then force a re-login to refresh the claims.