After entering the right credentials, putting in the new password, and clicking the button, the window closed for me. It did change the password, but there was no visual indication. When I opened it back again, it said invalid credentials to me. And I could log into the bank after that.
I ran into the same issue. It might be because you capitalized the password when you typed it in. I restarted the game and didn't capitalize anything and it worked.
