Can't login to admin when upgrading from 3.9.1 to 3.9.3

Hi,

I’ve just tried upgrading from 3.9.1 twice but each time the upgrade seems successful but when i try to access to admin panel or ANY user accounts

the password is incorrect.

There are no errors in the error log, i have also tried accessing the admin account by setting planPassword field and removing the encrypted version.

Please help, we really need to upgrade to 3.9.3 without starting from scratch.

Thanks
James