Currently, in-game clan/guild is named “OTG”.
Submit a NEW invite request (i.e. your own thread!) here as usual in General Games:
https://forums.oldtimersguild.com/c/gg/gg-in-game-invites 1
Don’t forget to mention which system!
Also, your Origin privacy settings need to be non-private so we can search for. Apparently, invites are all done through the app only 
We can approve invites via the mobile app.