Thompson, Martelli, and Shultz "Anthony Marcelli" "Barbara" Threatened to arrest me if I dont pay a company called CP investors who I cant even get a valid contact number for Baton Rouge Louisiana

On 12/8/2014 I was contacted at work by a "debt collection lawyer" saying that I owe “CP Investors” $550 and that if I didn't pay today I would go to jail and be garnished for $4000. I gave a man named Anthony Marcelli my debit card information and set up payments , once I did that he gave me a “court release number” saying that if anyone else tries to contact me about this debt just give them the court release number . After talking to a family member who told me there were fraudulent debt collection scams going on. I attempted to contact CP Investors to see if this debt was valid, however out of the 5 numbers  I found for this company , only one was in service and a lady picked up and said they were no longer affiliated with” CP investors”. I then looked on my credit report and found no creditor by that name. Anthony Marcelli sent me an email that had an incorrect home address so when I called to notify this "law firm” that they misspelled my address I also asked them if I would receive anything in the mail stating that I was making payments and "Barbara " the “paralegal” I spoke with laughed and told me I would get something once I paid the whole balance due. I have never received a validation notice in the mail saying I owe “CP Investors” and when I looked up the law firm that was on the header in the email  that I was sent I could only find complaints about Anthony Marcelli calling other people from different numbers in the same fashion and when I called those numbers they were already disconnected. The law office named on the email header is “Thompson, Marcelli & Shultz” the address on the email only has a P.O box in Baton Rouge Louisiana and when I looked up the business it was registered in New York in august of 2014. I don’t think this is a legitimate debt collection agency and if they are it is illegal to threaten to arrest someone if they do not pay a debt.  Anthony Marcelli has called my place of employment twice and threatened to arrest me for a debt that I know nothing about.