annoying calls

I am a customer to Homechoice for a while now, I have recently made purchases during 2017 and am still paying my instalments regularly, what is frustrating is that every month the Debt collection department calls to confirm when I will be making payment for the new month, I actually took of with the lady yesterday, cos I was at home when they called. If I was in arrears with my account then I would understand the reason for the call, however I am making my payments every month and am still getting the calls. I actually want to pay off the account and be out of their mailing list ( what is also annoying is that even if you decide to settle the accounts sooner, no discount is given to you, so you have to pay the entire amount of interest for 6 months even if settled earlier) Besides this you have the call centre agents who call 2 sometime 3 times a day with promotions!!! despite saying you not interested, you then get asked why?? seriously!! I like the products that you sell, but if having to go through this then Im sorry to say that you have just lost a customer...