When a debt collector contacts you, at some point in the conversation they must advise you that the call is from a debt collector in an attempt to collect a debt. At this point, you should not engage in open conversation. Especially DO NOT admit the debt is yours, regardless if you believe it is or not. Here's why...
Many debt collectors trick consumers into verbal contracts in order for them to pay on debts that they may not be legally obligated to pay. You should always request that the debt collector mail you any information in writing they are accusing you of owing.
It is to your benefit to maintain a call log of the incoming calls from debt collectors. If possible, write down the time of the call, name of person you spoke with and any other information you deem is relevant from the exchange.
If the debt collector is violating the FDCPA, you may file a lawsuit against the debt collector (which costs you nothing) and receive $1000.00 for statuary or more for actual damages.
§ 806. Harassment or abuse [15 USC 1692d]
A debt collector may not engage in any conduct the natural consequence of which is to harass, oppress, or abuse any person in connection with the collection of a debt. Without limiting the general application of the foregoing, the following conduct is a violation of this section:
(5) Causing a telephone to ring or engaging any person in telephone conversation repeatedly or continuously with intent to annoy, abuse, or harass any person at the called number.
(6) Except as provided in section 804, the placement of telephone calls without meaningful disclosure of the caller's identity.