Russian T-95 Black Eagle tank

Hello PR community, so this is my very first model that I've worked on for a few months now but when I tried to put it ingame it gave me an error.













I don't really know what the error means and I have no idea how to fix it so I came here for some help.

If in case the pictures dont show up (i dont know why/how) heres the error message:

"The PCO of Template Cupola is not accessible"