Replaced Screen, Get full signal but can't make or receive calls

I replaced the Front Screen on my iPhone 4S Sprint. Im getting full signal, 3G is showing as active, but Im not getting or receiving any phone calls. Text messaging doesnt work either. I even tried dialing 611 with no avail. When someone tries to call me, my phones going straight to voicemail. Any ideas? Ive searched the net, can't find anything. Sprint claims theres an outage in my area, but someone next to me with a Sprint phone has no issues. Plus as I said, im getting 3-4 bars and 3G is showing. I attempted a reset of network settings as well as reset all settings as well. Even tried a soft reset.