https://nl.ifixit.com/Answers/View/107212/When+plugged+up,+DS+won't+charge
OPGELOST: When plugged up, DS won't charge - Nintendo DS Lite - iFixit
Venessa, I would check the charger and make sure that you have the proper voltage coming out of the adapter. Check the charging port with a multimeter and see...
plugged upopgelostds