This happened to me before and I think I just kept trying and it eventually worked. If it won’t let you do it yourself you can always call the enterprise help desk and they can change it for you.

Happened to me the other day! Call the partner help # and they should be able to give you a temp password.

You need to reset the password from BOH computer or store iPad. You must have finished your work anniversary recently and it prompts you to reset the password when you try to sign in