Why can you only play online dawn of war soulstorm as two races AKA dark eldar and the sisters of battle or witchhunters Only joined online recently.

it is because you need to purchase the : Dawn of war Dark Crusade in order to unlock Tau and Necrons. Dawn of war Winter Assault to unlock Imperial Guards and at last Dawn of war ( The First Game ) to unlock Space Marines , Chaos , Eldars and Orks And after that you will need the Keycode of all of them and activate each one when the time appropate