Hello,
I have built a flow that allows users to initiate an approval flow on a document from a document library. The flow has been working fine for a couple of months, but now users are unable to use the flow, the "Run Flow" button is grayed out as you can see in this screenshot from one of my users:

I tried deleting the flow, and recreating it from scratch thinking that something had broken over time, but it has not changed anything. Currently the users, including the user that this screenshot is of, are all owners in the group workspace, that this flow is to be used in. As I said, this used to work up until about a month to a month-and-a-half ago.
Any thoughts would be highly apreciated.
Best regards,
Dan