I have Samsung Galaxy J1 and incoming calls from one particular number sometimes will come through but most times (95%) will maybe ring once or not at all and get sent directly to voicemail. This is usually happening with calls during the daytime, evenings calls tend to come through and ring so I can answer. Doesn't seem to make a difference if I'm using wifi connection or not. I don't know if its a phone problem or internet problem.
jobug642, I am sorry to hear you are having issues receiving calls from a certain number. bearone21, brought up a good point do you know if this number is blocked. I have included a link on how you can check. I hope this helps. https://www.verizonwireless.com/support/knowledge-base-158063/
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