Caravans at the Sunspear 2.51

[berkcemal]

lots of caravans and also two lords of mine, theyre sailing from port of sunspear and then quickly returning back and they making this cycle like forever. i believe this is a bug. how to fix it?

edit: i realized all the caravans are trying to go volantis, my capital. but they cant. they turning back half the road. is it something about my kingdom?