OAuth Client Setup - Wrong Protocol

We register an app with HTTPS protocol for Oauth2 on Gitea. The application data in the DB table, oauth_application, shows the protocol correctly. When a user signs in from the OAuth client app, log messages on Gitea show the protocol of the redirect URI is HTTP instead. A user can’t sign in to the OAuth client app as a result. I guess that won’t relate to a data cache that changes the data from the DB. Is some sort of configuration in this regard?