I called and talked to Customer Care about this issue and they said it has either something to do with the phone itself or the cell towers...I told them that people will call me and when I hear the 1st ring on my phone it will go to voicemail for the person calling..They told me if it happens then just soft reset the phone so it can search for another cell tower and hey they started my nights & weekends @7pm for free LoL
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