Having a problem where a number of users are trying to access SharePoint libraries via the iPad files app (they have their reasons to do it this way) but the sites are not showing in the libraries app. They have the exact same permissions as other users in their team and they can see the sites in the OneDrive and SharePoint apps. I have signed in as other users on their iPads to rule out a device issue and it works. Same goes for me as the Administrator signing in to their iPads, works straight away.
I've tried the troubleshooting by signing out, deleting apps, installing again. Even changed their permissions to owners etc but no change. It's the same on other models of iPad and iPhone too.