Extremely bad debt collection agency

This company does not deserve one star even.They are ineffectual badly run and even worse trained.I received a legal notice threatening legal action and rep**** with proof of payment made last June enclosing proof of payment.They rep**** giving me a ticket number and advising me they would give my query their best attention. Needle to say I heard nothing but guess what received and even more threatening letter advising me that they would throw the book at me if I did not pay.I have paid.I sent POP. An answer is now required not threats.