u/Hatemobster

So I own the game on steam and own it on ps5. I'm trying to play zombies with my girlfriend on separate setups so we each have our own screen. The issue is my Activision account is linked to both the ps5 and PC. You cannot be logged into both at the same time. What is the easiest solution here? I've tried unlinking my Activision account from PlayStation and it gives me error messages. Just trying to play together.