My Cash Now scam collection agency calling me at work internet

I received calls on both my cell phone and my work phone from first a 'Special Investigator' from a collection agency saying that Bank of America bought out My Cash Now for a payday loan I supposedly had with another bank from like ten years ago. I said I had no knowledge of the loan and that I hadn't had that bank account in years.

The 'Special Investigator' REFUSED to provide me with any documentation regarding the supposed loan, despite me asking him repeatedly for it. His supervisor, another 'Special Investigator' also refused to provide me with documentation, stating he wasn't allowed to put that in an email and would not postal mail it to me.

I told them both there was no way that I was providing payment information on an account I had no knowledge of and they even threatened to have me arrested for it.

Once they started threatening me, I hung up.

Weeks later, I received another call at work and told them they were no longer allowed to call me at work.

I gave them my cell phone number again and this time the person was 'Paralegal' Something - it was clearly the same gentleman as he has a unique and distinct voice. I explained to him what happened the last time on the phone and he stated that I had NEVER talked with someone from their office - even though it was the same phone number calling me - and that all I had to do was to ask for the paperwork. I explained that I had and they refused. He stated that was false.

I said fine, then I am asking you now to email me the documents - and now still, nothing. Just a threat of 'what's going to happen at four o'clock today and I don't want to embarass myself.'

I am now on the phone with my company's legal services to see what can be done.