This number called me 2x and didn't leave message

This number called me 4 times today and never left a message

This number has been calling me for a week now. When I answered, they knew my name, full address, and number. He said he was a debt collector and was asking for payment. I told him not to call me but he hasn't stopped. I'm not sure what is going on

Since he already contacted you via phone, he now has five days to mail that initial dunning letter to you, per federal debt collection laws.  If he refuses to do this, you can be sure it's a faker.  The FTC has more information here, at the link, on how to tell if a caller is legitimate or not: https://www.consumer.ftc.gov/articles/0258-fake-debt-collectors