I declared war on the king's house Swyft with the casus belli "seize the iron throne" playing with Westerlands. Once the war is won, after the peace treaties, it makes me play with the house I won against. I keep the Lannister dynasty I played with before, which becomes king and no longer lord, but I lose control of the Westerlands territory and army, I also have all the penalties of the house that lost. Why? I should continue with Westerlands and the Lannister dynasty