The A/C is blowing cold air out of the passenger side vents and warmer air out of the driver side vents. I had the refridgerant topped off but the problem still persists. Any ideas?

I had this problem about 2 years ago. You probably don't have enough refrigerant. I recharged the system and solved the problem.

Look at the small glass window on the top of your receiver/drier while the A/C is on. If you see white creamy stuff, then you need more refrigerant.