Fx20 ebike

So I just got this ebike and already messed it up. I plugged a portable charger into the screen and shut the bike off. Now I just have a blank screen with four zeros on it and I can't do anything. The bike won't go turn on or anything at all. I'm sure there's a universal code I can put in to make it boot back up. But I have no clue what that might me. I've tried googling several different default boot up codes and gotten nothing and I'm really hoping I didn't just flush 700 dollars down the toilet. Any help?