So i have noticed this a few times now on multiple maps i have.
A few things i have seen so far are;
1) When stacking and then unstacking rovers the unstacked rovers lose their "functions" the only menu option they have is the red "x". this can usually be fixed by building something the rover is able to build then after its done the menu returns to normal.
2) Game thinking the lander is something else. I have attached the map i got this error in but to sum it up i have been slowly moving all of the landers to one map (not easy when some of the landers are messed up like in #1). I was messing around trying to get the lander to move so i sold some of the surrounding buildings hoping the move option would show back up then suddenly the option to sell it popped up and after clicking it it showed the option to sell another stargate???
@bastecklein