Level 1

upgrading from qb premier 2015 to 2020 - problems

I recently migrated to qb desktop premier 2020 from qb desktop premier 2015 but am having problems with the admin id/password.

1.  With several of my qb company files, upon opening  them, I was prompted to enter the admin user credentials.  When I did that , qb rejected them. 

2.  So I tried removing the admin password (set to blank) from qb 2015 and then retried opening the qb company file in ver 2020.  qb now prompted me to create a password for admin and set my security questions- which I did - and it proceeded to convert my company file for the new version.

3.  I can now open these company files with all authorized user ids but the admin credentials, again, are rejected.  The security questions I set do not work either.

Any idea how to fix this problem so that I can have admin access to my company files?