I have similar (but not identical) permissions problems. They seemed to coincide with the update of Wordfence to 6.1.2. I do have the User Role Editor plugin but that was last updated 17 March and I haven’t seen any problems since then until now.
/wp-admin/options.php gives me a page of info headed “All Settings”.
/wp-admin/network/ gives me “You do not have sufficient permissions to access this page”.
At the top of the dashboard I see the message “WordPress 4.5 is available! Please notify the site administrator” when I’m logged in with either of my Administrator accounts.
I can create a new user with Administrator role although none of the solutions here has worked for me.
Can I just confirm that when we’re talking about editing users here we’re referring to the “Edit User” screen, changing the Role (in some cases) then hitting “Update User”?
I do have Wordfence 6.0.25 installed on another site. To revert can I just copy the plugins/wordfence folder from that over the top of the same folder of the site with Wordfence 6.1.2?
Any help appreciated – thanks!