caller was rude and kept calling back after i told him to stop calling

Caller wanted to know how I'm doing today and then told me I was selected to receive $100. Only had the Iphone a few days and I'm getting junk calls that can be charged to my service already!

I received several calls from this number and missed the first 2. upon calling it back i get a disconnected number tone then the female voice telling me this number is no longer in service. Once I caught this number calling me I answered and got nothing but silence then it hung up. Best thing to do is ignore numbers from unknown area codes.