Has called twice a day for several days. No message.

I have received numerous calls from this #.  The ID says Starnet, Inc. Today 01-23-14 I have received 3 hangups with no message left.  

I have had several calls form this number over the past few days.  No messages left. I called the number and got a recording about a Walmart or Target gift card.  I did not trust them so did not request the gift card.  Afraid of identy theft, so I just hung up.

I get around 5 calls a day. Once I answered and it said something about a gift card from Walmart. If I wanted it, I was suppose to press 1, but I didn't. How can I get them to stop calling?

Today is the first day that I have started receiving phone calls from this #.  They have called twice today, but no message.  I also called back, and the recording said that I could get a Wal-Mart gift card.  I am tired of all these garbage phone calls.  I have an unlisted phone #, so I don't know how these people got my #, so I just blocked them from my phone.  So, at least now, my phone will only ring once, and on the called ID, it will say "caller blocked", but then it will show who called.