GLITCHED PSVITA

I just powered on my vita after maybe 5 months of not playing on it, and it wont even let me do anything for more than 5 seconds before it freezes and doesnt let me do anything on it, i tried taking out my microSD and putting it back in again, but now it doesnt load anything i have again. What should i do? Do i need a need microsd? Could someone explain whats happening?