I also have this sh*tty issue. What's more annoying is that this doesn't fix itself automatically.
This is mostly because of EA App and EA Background Service. Whenever it occurs, I just use the 'clear cache' option from the EA app or completely stop the EA background service from the taskbar.
When I checked the reason for it, they say you can't play a game on multiple devices at the same time. Also, logging in to multiple devices can be the reason for this. The funny thing is that I only use one device. That doesn't make any sense. And then I checked my login devices; they counted the EA login from Steam as another device. just like a browser login.
It seems like EA Background Service counts Steam as a different platform. They don't count it as a PC. which is why, when you play Apex on Steam, the EA background service detects it as a different device. and thinks you're playing Apex on multiple devices at the same time. So it's neither your fault nor respawn, its actually because of EA app.
I don't know why nobody complains about the EA App's sh*t performance. it is worse than Origin
Recently, it occurs every second. which is completely annoying. Not only that, the server pings are showing wrong in the main menu as well. I think the EA app, Respwan, and Steam should sit together to fix this problem.