Highly Frustrated with their constant calls

Good day sir/madam<br> Seven months ago I made arrangements with Mbd of a russels account for R400 to be paid every month, ever since I have been paying and haven't jumped no month without any payment. <br> Besides to making these payments their call centre never stopped calling me sometimes I get ten calls in a day I have spoken to them on numerous times but they have told me that it's within their obligatory to call people whether they made arrangement or they are paying, they told me that they can only stop calling once the debit is settled. <br> <br> This makes no sense to me and it's frustrating to the degree that I feel to just not pay anymore and change my contact details as they makes no difference to me and I get no peace at all. <br> <br> Kindly assist me for this people to get off my back. <br>