I have been missing calls. Phone doesn't ring or show that I missed a call. I have been to local store and got phone replaced because other things were happening now new phone still not getting calls. I was told about the Tri-band and tower upgrade problems. But I need to receive calls. I have a 80 year old mother who needs to be able to reach me. If the tower up grades aren't working with these phones we should be provided with phones that will work.