Total War: ATTILA

Total War: ATTILA

Medieval Kingdoms Total War 1212
Vassalage problem
i play as seljuk sultanate of rum and as expected all the crusader states declared war on me, after beating them + kingdom of cilicia, i managed to subjugate them and make them my vassals but problem is after they became my vassals they still seem to be allied with their previous allies (which are my enemies at the moment) and they are enemies with other muslim states which i have non-aggression pact with. is this a common bug? is there a way to fix it?