I have owned my Samsung SII for approx 18 months and have noticed recently (approx last 3 months) that my phone sometimes goes into a "frozen" state where it does not receive calls, messages or such like in spite of it appearing to be totally normal i.e. no error messages are displayed, full signal strength bars are shown. The only way that I know that something is wrong is when people start telling me that they cannot get through to me or that their messages are not delivering to me. If I reboot the phone all the "missed calls" and messages come through for the past period whilst the phone has been in this "frozen" state. When in this state I can still use the phones other features such as the camera or browse files, pics etc. Can anyone out there help? It would be much appreciated. It is very frustrating not knowing that the phone is in this "frozen" state. Many thanks.