Can't play with my fam member on same server. Need Some Help!!!!

[SKZortex]

So me and my brother are trying to play zombies together on a server, and every time we join a server one of us gets disconnected from the same server. it either says "error creating an online profile session, or straight up says " Disconnect from server". anyone know why it happens? it works fine with every other plutonium game but when we try to play bo1 it just doesn't seem to work and decides to kick one of us out while the other one stays in the server.