The very first main story quest (or maybe 2nd) should have sent you to the guild for whatever class you selected as your starting class when you re-entered the game (not at all related to any of your other classes). If you're that far along in the main story, you must have done that quest at some point, though I can't recall if you can skip the job guild part.

Given that Lodestone lists you as a level 1 Arcanist, I suspect you chose ACN as your "starting" class when you joined back up. Is the Arcanist's guild one of the guilds you've already tried?