I cannot sign in to Matchmaking at all. Recognizes my profile, starts downloading it then a 1/4 way in, it says my sign in credentials are not correct Which is absolute BS, since it recognized it and started the download…I also sign in here using same credentials…Other than that have been getting told Im not on XBOX live when I am...It will let me play a certain amount of games then kicks me out saying Im not connected.This has been going on for quite some time. I know hardly anyone plays this anymore and maybe they have given up supporting it at all?
I’ve had the same issue for about a year now unfortunately with Halo 4 kicking me out of matchmaking for “losing connection to Xbox Live”. What I’ve recently figured out that seems to work is after the first disconnect, I quit the game back to the Xbox dashboard, sign out, load Halo 4 and then sign in again. Once I do this it seems I’ve been good to go without getting kicked again.
Are you playing it on Xbox One? If so, try deleting and reinstalling the game. Sometimes back-compat games have weird issues like this and a reinstall tends to fix everything.