It seems like the main problem is coming from people that have unlinked one account and then tried to link another account to get that old progress back.
The same is happening with me. My main account is on xbox, and when I got a ps5 I made an entirely new ea account last season just to continue playing. This season I unlinked my new ea account I temporarily made on the PS5 and linked my old ea account from the xbox and now I can't access anything besides play and club, with only base legends unlocked.
I really don't care about anything from the new ea account, and I'm not expecting both accounts to fully merge since they are on 2 different emails. I'm only looking to access the content I had on my old ea account from the xbox.
Also the strange thing is right now some of the content I had from my new ea account from my ps5 is still merging. Like the current level as well as the badges I have on some of the legends are still here. While the club I'm in from my old xbox account is here as well.
I'll add a picture as well for more context, thanks