Error Message When Referencing Environment Variables in OAuth 2 Fields

when trying to set the OAuth2 parameters to pick up variables from my environments, this fails to get the token with the error

Plugin Error: Failed to fetch access token with status=400 and body={“error:”invalid_client”}

I can hard code the variables in those fields and that works fine. If I hover the mouse over the environment variables in the OAuth fields, the correct value is displayed so I can see that it’s getting the right data, but the request will always produce this error.

Thanks

Steve