Over the last couple of days, I have have missed at least 3 calls because they simply were not received by my handset. The phone does not ring and there is no notification that I missed the call until more than an hour after the call was originally placed. This happens while I have a full signal and I am even able to successfully place calls when experiencing the issue, as noted when one caller texted me immediately after trying to call and I was able to call her right away. Is anyone else experiencing this issue?