SharePoint Online – Choice field not saving selection

I have a document library in which there is a choice column set to all multiple selections. I have been recently made aware that when new items are added to the library, a selection can be made but that selection is saved once the upload is complete. Attempting to edit the library in Quick Edit mode will allow for one or more selections to be made, but they are not retained once you stop editing the library.

This is not a required column and there are no workflows. This is just a basic document library. Any suggestions of why it might not be saving the selection made?