I was helping a client with a permissions issue with Flow. The Flow would get triggered manually by a user to kick off their performance review. The problem was that some users didn’t have the option to start the Flow.
I went into the Flow to make sure that the SharePoint library had permission by ensuring that it was in the “Run-only User” list as mentioned in this post.
That didn’t work. So I got an end-user on the phone, and had her share her screen as I started digging. What I found was that even though the user had permission to her content in a library, and the user was also in the member’s group on the site she was missing one important set of permission.
In the library itself, the members group’s permissions were removed. Once I reintroduced the group with edit and contribute permissions, the user was able to select her flow from the menu.