Lawsuit

I received an email today stating a lawsuit was going to be filed against me un less I paid a settlement. The email stated that I owed $964.52 on a past due "payday" loan of $300.00.  My refusal to pay would result in my owing $2872.81(where do they get these number?)  in court cost and other fees.  I responded to the email and asked that my email address be removed from their contact list because I did not owe any "payday" loans. And if they continued to contact me, I would contact my local law enforcement.