ADSS password change option just refreshes page - does nothing. No errors

ADSS password change option just refreshes page - does nothing. No errors

All of sudden (about 2 weeks ago) the ADSS application just stopped changing passwords. (All other components seem to work fine).

when you try and change a password the page just refreshes quickly and that's it. No errors, nothing on the screen (and it has not changed the password).

INFO:
- using the domain admin account as the authentication account.
- no windows updates have installed on the server (it's in a DMZ).
- only using the 2 local DCs, no extras.
- no audit failures on the DCs either.

Any ideas? Anyone have any fixes? Support has been looking at logs for almost 3 days now.