RMS-Recovery Management Services, Inc. Debt Collection Complaint

RMS-Recovery Management Services, Inc. Debt collection department,

I do not know Disclosure verification of debt Not given enough info to verify debt California

I was contacted via telephone - of Recovery Management Services that I was in debt $4900.00. I disputed the amount and wrote a letter to the company asking for verification and sent it Certified Return Reciept Requested on - -, 2015. I wrote another letter asking them to cease and desist further attempts to contact me which was sent same method on same day. I got my return reciept back with signature - as recipient on - -, 2015. I am still receiving calls which I let ring and I got a notice in the mail that they are now willing to negotaite to settle but still have not proved I owe the amount they are trying to collect.