Can a collection agency add multiple bills togethe

Creditors often assign the accounts to the collection agencies when they are unable to collect money from you. In such a situation, the collection agencies contact consumers regarding the payment of debts. The collection agencies can refuse to remove the negative items from your credit report until the accounts are paid in full. They may also refuse to remove the items even after the accounts are fully repaid. They can just update the account status as "Paid in Full". But if you can negotiate a PFD agreement with them, then may remove the items from the credit report after the accounts are paid off.

I don't think collection agencies can add multiple bills together and collect the debts. They only collect the debt which has been sold off to them. You should negotiate with your collection agency so that they can give you a payment plan to pay off the debt.