Progress lost in cross progression

I lost all my game progress due to a cross progression issue, and multiple support cases have failed to resolve it.

I played apex on Xbox for over 1.5 years, then switched to PC before cross progression existed. When cross progression launched, my Xbox account was linked to an old EA account, so I unlinked it and linked it to my current EA account (the one used on PC). But when I launched the game, I was never given the option to choose my main account — it automatically made the PC account the main one, overwriting my Xbox progress entirely. My Xbox account now loads as a completely fresh account.