During state vs state event. If you teleport to another state your previous spot becomes a purplish..

In that case, you can't teleport back to your spot, you only tp back to the exact same spot, if the event is over and the game has to teleport you back to your respective state

Actually you can to to same spot, just use advanced to and position ur base over the one with purple shield. Its allowed if its ur base, I do it every ke.