I've found a bug with the command block. I was teleporting and i teleported myself to a coordinate. And i was teleported to a place where i teleported to another time. The chat says that i was teleported to 2 places. On the screen shot you see 2 coordinates. I teleported myself one time. On the other screenshot you see that i must teleported on the gold block. That is the first coordinate. On the tirth screenshot you see what is in the command block. This bug is in singleplayer.