SteveSpy , thanks for posting the screenshot.
I can confirm that after seeing the language contained in that screenshot that this is due to access being revoked and not due to a technical issue.
For anybody else experiencing something similar, you may have been removed from the section due to violation of the rules per the site administrator's
warning here (also referenced below).
This revocation of access also applies to other forum sections, where necessary.
A kind reminder that the best way to avoid this is to observe the forum rules.