Elevator is not working

 i believe im on current version, i play on xbox, not the old xbox edition though. 

I made a couple of elevators yesterday, first time making a flying machine elevator, did it from tutorials from mumbo and crayfish and myeeep. They all had the same problem!!! The elevator would get confused. It would go up a few blocks, go down a few, go up and then finally come back down. Rarely would it reach its destination. Mind you i created 4 different elevator designs and redid each of them like 3 or 4 times. To no avail of course. Im pretty sure im not doing anything wrong. So is it a bug