My 3ds has been not turning on

My 3ds has been not turning on for like 4 months, I tried taking out the sd card 100 times and I gave up and left it alone. Today, I finally fixed it, BY TAKING OUT THE SD CARD. Lol. Then later i wanted to set up wiimmfi on it, everything was going fine until I pressed done on my internet settings, then it froze. So now every time I boot it up and try to go back to settings it freezes 3: (btw this things literally never messed up like this its in almost perfect condition) if anyone can help I WILL BE ETERNALLY GRATEFUL because it was originally my sister's so if I can't fix it I'm screwed D: