All calls going straight to Voicemail
My phone was not on silent or anything during these times, I have full coverage on 3G and I just can't understand why this is happening now. I only sometimes will get an SMS notification of a new Voicemail message minutes after the caller has not gotten through and just gone straight to VM. Othertimes, it's days after until I get a notification that I have a new VM.
I've missed several important calls because of this. I have tried turning my phone off then on again but to no avail. I'm not sure of what actions to take next.
I'd appreciate any advice, thanks!
iPhone 3G, iPhone OS 3.1.2