Roon assigning the same wrong album art to new albums

Just recently, Roon has been assigning the same incorrect album artwork to albums I add. I’m relatively new at trying to fix metadata issues. Before Roon, I was using iTunes exclusively, and while there were occasions where no album artwork was provided, I never had to deal with having to manually edit so many albums. Having noted some Roon users’ success with MediaMonkey to organize their libraries, I used it to re-tag my entire library. This didn’t fix the wrong album artwork problem, and now I have a lot more albums without any artwork than I had before the re-tagging. I’ve tried using all the suggestions about changing import settings, etc., that have been offered on this subject by Roon users. I note this is a fairly regular problem in one form or another, with Roon users. My library is housed in my iTunes library. Please help as I have no ambition to manually edit the artwork of hundreds if not thousands of albums (3tb library). Thanks in advance.