Your rights to dispute debts do not change simply because a lender sells your account to a debt collector. Lenders and creditors may sell debts to collectors rather than spend additional money trying to collect the amount owed. This way, the lender can recoup at least some of the money you owe and offload the debt collector duties to a specialist. Some grounds for dispute include: The debt is a result of identity theft or other fraud. The creditor took too long to attempt recovering the debt, so the facts and underlying paperwork are lost or forgotten. You repaid the debt without receiving acknowledgment for doing so. On the other hand, an unscrupulous credit repair service may claim that it can remove legitimate debts reported to be in collection. This is a tipoff you are dealing with a bad credit repair company. When you file a debt dispute with a collection agency, it must stop collection activities and investigate your claims for 30 days. If you find yourself being harassed during this period, you can file a complaint with your state’s attorney general and with the CFPB, either online or by calling 855-411-2372.