NCB Management Services, Inc. Debt Collection Complaint

NCB Management Services, Inc. Debt collection department,

Credit card Improper contact or sharing of info Talked to a third party about my debt Florida

I was contacted by this person that claimed he had purchased my loan from another company in which I had been paying on for over 6 months by auto draft from my account. This guy proceeded to tell me that he needed me to give him my account information so that he may continue to draft payments from my account. Needless to say I refused to give my information out over the phone and since then he has continued to harass me, calling constantly - times daily. He has also contacted my sister and my mother which is unacceptable. Is there anything that can be done about this?