Nether portals not linking

 In a Minecraft world I have been playing for a while all of a sudden the nether portals do not link.  I go in my nether portal and I end up in a place I never been to and when I go back in I go to another random place in the overworld. A day later I go in and it is fine ,but when I come back out I go somewhere like a thousand blocks away no where near a nether portal and just makes a nether portal for no reason.

        I have no idea how idea how I did it but all I know is that I built A LOT in that world and was glitchy.   Coordinates from -477 64 1117  to -60 72 124. I tested it again and it is fine. 

         I have found out how to recreate. Fly in with elytra without touching the floor and come back without touching the floor and now I am back at my ship 1,000 blocks away. Why Idk(Only well works in creative) Also I shared a video on the Xbox if that helps.