got a call and they just hung up what is it?

Called the number back and it said bad number unable to call number you've dialed.  Who is it?

Have been getting calls from numbers like this for a week. Caller calls from a different number everyday and when I call back it tells me the number is wrong.

Did not answer because this number is not entered into my phone. No message was left and not planning on calling it back. Not important. And calling at 9pm? No thanks.

Called back and it said incorrect number.