So, I had completed the Shaymin quest long ago and finally decided to train it to use against bosses. Using Shaymin-Land I fully EV trained it aswell as teach the moves; Synthesis, Seed Flare, Ice Beam and Scald.
Now, when changing it to Shaymin-Sky I lost all of my moves and now I just have tackle. I am aware that Shaymin-Sky is banned in PvP however, I don't believe this should have happened.
When inspecting the move relearner, Shaymin-Land has the ability to re-learn all of its levelled moves however, Shaymin-Sky did not.