Have you checked to see if Windows Update has installed a AMD driver since you installed the current AMD driver by any chance?
In another words, do you have Windows Driver Update disabled before installing the current AMD Driver?
The only thing that comes to my mind is that there might be a leftover Driver Installation Registry concerning your previous AMD driver that is causing your problem.
That is why I suggested you use DDU which, I believe, deletes Registry entries in the Registry besides deleting all AMD Driver related files.
Otherwise, If any other Users doesn't have any newer suggestions then try opening a AMD SUPPORT Ticket and see what they suggest from here: https://www.amd.com/en/forms/contact-us/support.html