KID from well-known configuration not present in access token

I am following the tutorial for flask by auth0, and I am currently not able to find the KID from the .well-known/jwks.json that is contained within the access token sent to the server.

Does anyone know why this might be the case? I am sending the access_token as the Bearer Authorization token to the backend.

The problem turned out to be Google ESP:

My information flow was architected like so:
Client -> ESP -> View Service -> Deep Service

The Client was sending the correct access token, but the view service was logging the wrong access token. I confirmed the view service was getting the correct access token after contacting the view service directly rather than going through ESP.

I solved this by using the Auth0 integration with Google ESP: