INSANE BATTERY DRAIN PLS HELP

just charged my garmin 255 music to 100%. 40 minutes ago. 96% battery. no kidding.

battery lasts 3 days and it's gone. I've  disabled garmin share, wifi, EVERYTHING. 

I've been asking garmin to help me, but I'm in brazil and they won't help. 

firmware: 20.31. 

it's insane. 3 {moderator removed profanity] days. I've tried anything that is possible.