Bug that needs fixing

It is a good game, however, the game started to delete all of my upgrades that I had put into it and bring me back to wave 21. I have tried to get beyond that specific wave and it will work for approximately two days of playing, but then it erases all of my upgrades again and put me back at wave 21. Please fix this bug. Otherwise, it is fun and entertaining.

Oh Yeah 95 about Samurai vs Zombies Defense, v3.0.1