Erased all my data

Ive played the game for a long time now. I built an impressive team, hard earned through hours of playing. I go to play the game today and to my horrid surprise, Im suddenly playing the tutorial again, and all my monsters, all the levels I had beaten, and everything else was gone.
DO NOT PLAY THIS GAME! IT IS A MASSIVE WASTE OF TIME!

Qmanzo about Monster Strike, v5.4.1