Sometimes when iam flying using mount or flying master, i get dropped off the mount and i keep getting Transfer aborted, instance not found and i cant mount back up. Cant use hs or portals or dungeon tp or accept summons or enter dungeons/raids.
If u cannot do any action ingame, then close game client, close desktop app.
Start the app then the game.
IF this isnt work so far, then restart modem too (wait with 4-5 minutes with plug in again to the electric system).