When a debt collection agency contacts you regarding an overdue debt, there are several things they’re legally obligated to disclose to you:
The name of your lender
How much you owe
That you have 30 days to dispute the debt — you can do this by sending a letter of dispute
Once you send a letter of dispute, the debt collector must provide you verification of the debt — if you request the name of the original lender, the collection agency must provide that as well if it’s different than the current lender