Magic Forums

my mother always walks in and out my room even when I'm gone and sometimes I can't find anything.
She takes sometimes stuff without asking 'cuz she thinks I don't use/need it anymore and sells the stuff then.
I need a spell to lock my door 'cuz I asked my mother for the key but she didn't wanted to give it to me, so it would come in handy.
But mention how to break the spell to plz. 'cuz I want to go in or outside my room sometimes and not be locked in or out without the possibility to walk out.
I would really be gratefull if you guys could help me.
grtz