Complaint Review: Wyse Finalcial Services - NCO Portofolio Managmement

Got a letter from this companies, telling me that I owe $7385.35. I do not acknowledge this debt to be valid or real. Made business with the late MBNA, now Bank of America. Close my account in good standing. Never received a letter collecting this debt nor contacted by phone. Now this companies want me to pay them for something that's either been paid or is not real. Is this the new way to make a living and fortune in America? Why the federal government and states allow this companies operate to scams/frauds consumers?

Jacob
Barranquitas
Puerto Rico