Photoshop 2021: Program Error when trying to save older photoshop files (something with layer mask)

Painstakingly found out error has something to do with my layer masks are getting "corrupted" when opening files.

1. Open file in 2021 (file created prior to 2021)

2. Save file, even when I make no changes I get a program error and can not save.

3. Delete problem layer mask(s)

4. Now it will save.

When I open in 2020 or 2019 the files will save no issues.

notes:

• So far has always been a layer mask on a shape layer, not sure this is relevant or not
• Shape layers have been duplicate shape layers with different layer masks
• There are 2 layer masks that have been corrupted on all the files, and both "Corrupted" masks need to be deleted to make it work.
• Moving shape and "Corrupted" layer mask to a new file will still not save