Rude and threatening call

Good day, I am in financial trouble due to a bad business deal late last year. Currently I have no income and am trying to get a job. I have been open and e-mailed everybody who asks me for many with the details. This morning I was phoned by a gentleman purporting to be from MBD attorneys. apparently on behalf of FNB. He claimed that he was offering me a solution. When I explained my predicament and reasonably asked him to e-mail me so that I could send my explanation and details of my situation he became most threatening and very rude. One would surely expect a more professional and sympathetic approach from a company who is representing a multi national like FNB!