Collection agency purchased the debt

The creditor won't accept payments from you after selling it to the debt collector. You will have to deal with the CA only because they are now the current creditor. Make them validate before a payment arrangement is done.

How old is the account? Maybe, you should check the SOL period and if it's close to be removed from your credit file as per the FCRA laws.

When a debt is sold it means that the company severed all ties with you and will refuse to work with you as they are no longer the creditor of the account.

I would also check your cr to see what on it.Definitey have any debts that were sold from oc validated.Some of these debts are sold many times. If you pay on any of these you want to make sure your paying the correct company and amounts.

If the debt has actually been *sold*, then you'll have to work with whoever is the current owner of the debt. However, whenever anyone tries to tell you that they are the owner of the debt, be sure to ask for proof before proceeding any further. Some CAs have been known to lie about owning a debt. (Among the many other things they're known to lie about.)