ethical?

i wanna know who this company is and if it is reputable. I have no idea who this debt they say I owe is from all I have is an account number and a dollar amount. I dont have an outstanding debt in this amount to any creditor and I have even checked my credit report and it still doesnt list this dollar amount. Very questionable for sure and why would anyone just start sending money to a management company without further information in regards to the actual creditor who is employing this company to represent them? You would think the company whom is owed the money would contact me themselves first but has never happened. Not ethical in any way.