Can't use REQ

I remember reading a few threads about this awhile back, but it still happens to me. Does anyone know the reason for this? I know a simple fix is to re-start my system (works every time) but I’m curious to know the reason for this problem occurring.

This still happens to me as well, and it sucks in Warzone Firefight. I think it has something to do with server issues, though I don’t know for sure.