I didn't answer either !

I thought it was the area code of a friend of mine so I answered it. Turns out they were looking for someone by my name who owned a Chevy TrailBlazer. Don't know if it was collections or recall notice or something else.

Called the number back and got the company name.

The calls are coming from a company called Scotia Dealer Advantage, formerly known as Travellers Acceptance Corporation, which is located in Vancouver, BC in Canada.  They deal with auto financing for people with damaged, little, or no credit.

They called me and I answered and they hung up right away..

I highly suggest to not answer the call especially if you have had your vehicle repossessed. The moment you answer their call you are then considered "under negotiations" which will allow them to take legal action on any if not all of the remaining balance of your loan. Example, sued for the amount to be paid immediately or garnishee up to 75% of your wages.