I am billed yet service was confirmed terminated

<br> I have sent several queris asking why after cancelling my contract in December i am still being billed for servises i am not recieving and i am only getting automated response to say that my query will be attended to in 5business days.<br> <br> In the meanwhile i get threatening summons with money i don't owe ..I paid this amount which i don't even know what it is for because i was threatened with blacklisting<br> <br> Please can someone assist