First of all this is quite a weird bug, it happened to me several times in a game then stopped happening for a few games and then happened again.
I would deploy my AT gun to the field, wait for it to get into the position I want, and right when I click unload from the truck, the gun dissapears and spawns the bottom of the map wihout a truck. This kept happening with both the M5 GUN 57mm and M1 GUN 76mm. When I played with other battlegroups the issue was not present, but if I chose the 3rd Armored Group it keeps spawning my field guns at the end of the map.
I would deploy my AT gun to the field, wait for it to get into the position I want, and right when I click unload from the truck, the gun dissapears and spawns the bottom of the map wihout a truck. This kept happening with both the M5 GUN 57mm and M1 GUN 76mm. When I played with other battlegroups the issue was not present, but if I chose the 3rd Armored Group it keeps spawning my field guns at the end of the map.