My Sharepoint Document Properties panel is stuck on spinning wheel - loading

[keetkdoh]

I have created a document library that has a content approval structure.

Team members input some additional metadata fields (columns that have been created within the document library) and click 'submit for approval'.

The problem we are having:

Some team members cannot access the properties pane without it getting 'stuck'.

When the 'i' (information) button is clicked, the side panel opens, but is 'stuck' on the spinning wheel (see screenshot).

Is there a workaround for this?

[#2]

Also having the spinning wheel issue in the metadata details pane, you can see that thread here: https://techcommunity.microsoft.com/t5/sharepoint/is-there-a-limit-on-the-number-of-content-types-al...