Rek'sai tunnel bug

I was just playing a match where the enemy team Rek'Sai used her burrow and the tunnel was not registering on her passive and could not be destroyed the player was using the tunnel to get into our base easier abusing the bug. The tunnel was on red side on the wall near the wolf camp. One side was some how cut off and she was still able to ult to that location (While I was standing on the tunnel).