.mov have become corrupt

i have tons of video from 1992 on—recently discovered that many of my .mov files are now corrupt and quicktime will not play them—have searched the internet and even spent money on software that supposedlhy repairs .mov files, and the results are: not work….fortunately the video that has become corrupt is raw and unedited and i have the edited versions on separate hard rives, but am becoming nervous that they too will become corrupted. some of this is 4K video shot with sony for-ax100. any similar problems out there?