No movement with added aircraft

Preinstalled vehicles have no issue but say the added B-25 works fine on my side if i spawn it in but my son’s side it just shows it siting still where it spawned in and its the same way if he spawns it in on my side it does the same as his,. if you change cars into something else it will be back to normal. It worked fine once at random but other than that one time it never seems to work.

I run a server and client on my PC and a client on his pc.