Lost my progress!

I am posting here hoping to find an answer. Upon completing the Festerville Hospital event, I received my rank (about 200) reward, (the + energy mask), played for about 20 mins, then exited the game. About a few hours later I begin to play, to my surprise took me to the Customize player screen from Level 1! What happened? Man, I was at level 19, so I needed to level up to 23 to even use the event rank reward mask.

Is there a way to restore my progress from an earlier save? I use a Kindle so can't use a SD memory card, but is there some option for Kindle users to restore?

Has this happened to anyone else? Any response is appreciated.