Asked by Scott Hemmeter on Aug 13, 2024
Scott is experiencing 400 errors when calling the custom workflow action callback completion endpoint (/automation/v4/actions/callbacks/complete) starting around August 12th/13th.
Answered by Lew Talon
Lew confirms experiencing the same issue. HubSpot later acknowledged (via Lew) that a recent change to validate callback IDs caused the problem. HubSpot reverted this change, resolving the 400 errors.