I made Enterprise Account with my personal Email,

And Salesforce Appexchange Package is Installed well,

I also Authorized custom app with all the way of authentication (JWT and others)

Service Account is created well,

BUT, when I tried to log in Admin or other user account on Salesforce Org, then I got error message like "You may not log in with an enterprise that does not match the service account. AccountId for User 1250805553 AccountId for Service Account null".

How Could I solve this problem?