Shg-a707 i just bought my phone today and when i put my sim card in it and turned it on the signal bars turn gray and the phone says "for emergency calls only

Phone is horrible.... I've been fighting w/ it for a year!!! I get the "emergency calls only" EVERYDAY .... the only way to remove it & get phone working again is to turn off. I have also removed the battery, & cleaned the sims card several times, still no help!! I have already done a warranty exchange and problems are actually worse than before. I never had so many dropped calls or "emergency only" problems with any other phone. I have actually switched phones w/ my daughter & I am using my sims card in her phone (Sony Ericson slider) and have had absolutely no problems at all!!! I put her sims card in my (Sync SGH-A707) and guess what....... yeap... same problems as before!!! Go figure..... My advise is to Go trade it on another phone before your 30 days are up..... this phone is HORRIBLE!!!! Phone is horrible.... I've been fighting w/ it for a year!!! I get the "emergency calls only" EVERYDAY .... the only way to remove it & get phone working again is to turn off. I have also removed the battery, & cleaned the sims card several times, still no help!! I have already done a warranty exchange and problems are actually worse than before. I never had so many dropped calls or "emergency only" problems with any other phone. I have actually switched phones w/ my daughter & I am using my sims card in her phone (Sony Ericson slider) and have had absolutely no problems at all!!! I put her sims card in my (Sync SGH-A707) and guess what....... yeap... same problems as before!!! Go figure..... My advise is to Go trade it on another phone before your 30 days are up..... this phone is HORRIBLE!!!!