What Version of the library are you using?
20.0.1
Question
With the version 20 the library checks the issuerUrl provide in /.well-known/openid-configuration document with the provide well-know URL. If this does not match an error is thrown like
[ERROR] ##REALM'' - Issuer mismatch. Well known issuer https://URL/auth/realms/REALM does not match configured well known url https://ANOTHER-DOMAIN/auth/realms/REALM.
Is there a possibilty to turn off this validation?