PDF files corrupt iCloud Drive
I have some PDF files stored in iCloud Drive since last year which seem corrupt.
I wanted to open them today but when I double-clicked nothing happened. There is not even a little cloud symbolising that they need to be downloaded from iCloud. When I try compressing them it says that "The file couldn't be opened because there is no such file."
It definitely can't be due to a lack of iCloud storage because I've got more than 1 TB still left. This happened to all PDF files in that folder that are larger than 1 MB, I've got some with >900 KB I can open and one with 1,2 MB that I can't open. What can it be due to? I don't remember having had any problems in this last year for any other files.
MacBook, macOS 11.3