Administrative Enforcement Notice - Threat of Lawsuit for Unpaid Debt

I received an email on 9/13/19 from American Financial Group stating that I owed $1280.00 ($400 principal; $880 int.&fees), this email included personal information and a former address. I sent an email back requesting more information on the supposed debt and requesting copies of the original documentation.  I got an email informing me that someone had "taken" a payday loan out on 4/14/17 from a company called Cashnet USA (was not given what location), a bank account number, and a bank name. I was informed in this email that if I did not take immediate action to resolve this debt, I would be charged $4,000 court cost along with the $1,280 debt.  After doing some research I found that American Financial Group is not a collection agency but is an Insurance Company.  I also researched the information that had been sent back to me and found the following:  1) I again requested that this company send me a copy of the original documentation, 2) The Bank Account was a joint account with my ex-husband and had been closed since 2011   3)I also let the co. know when I spoke with the bank about this acct # being used to acquire a payday loan  the bank would be looking into possible legal action. 4)  I again requested to know where this supposed loan had occurred since the only address, I had been given was one that I had not lived at since December 2012.   5) I stated that I was going to file a report with the police since either someone had stolen my identity, or my ex-husband had illegally used my information to acquire a payday loan.  6) I would also be contacting the Attorney General offices of the states where I presently live, where they show I was living at the time of the loan, and any address I can find for them.  I have not heard back from them since this last email was sent.