Piston Switch sometimes not working

This is a basic mechanism in minecraft & I was really upset to see it not working just like on pc version. See the attached screenshots for more detail. The redstone block has to change position EVERY single time I press the button and go back only when I press it for the second time (check the PC version). But MCPE returns it back in ~7 out of 10 times. Although sometimes it DOES work properly, but NOT always. I'm trying to use it in my elevator as a switch that could be accessed from several different locations (as long as buttons create singnal and then shut off, but levers do not so that I can't use them). But because of this bug my elevator gets stuck midway