Are you perhaps in the Yin Tower instead of the Yang Tower right next to it?
The magic hexagon is on the floor in the cellar of the Yang Tower, on the left side. There is no locked gate in the Yang Tower,
forgive me if I was confusing but yes im in the Yang Tower and when I went inside (activating the magic hexagon) to find the King I cant get through the magic door/gate I know how to get through by busting the magic generators (because ive played this before in my pc) but for some reason there isnt a option for that either im mising something or i think its bugged oh yes im using my phone