GPT Actions Custom API Key header returns 400

[aiko8]

I think this is a same issue.

Connecting Custom GPT Action to Youtube Data API with API Key Not working - Failure to pass Key to YT Data API with schema

Hello, I have been trying to do some basic testing using the Edit Actions in a GPT and creating a simple schema. I have generated an API key with Google, loaded it in the Authentication as an API Key, and tested it. Every test fails with a reference to an authentication error. I have tried to update the schema multiple ways, but no matter what I do, the custom GPT is not attempting to send the key with the request, causing the failure. I appreciate any hints as to what I am missing here! He…