Everyday phone calls and unfounded listings on credit record

I took out cell phone contract with Blue Label Connect. From the moment I took out the contract I started receiving phone calls from them. At first 1-2 a day, but then they phoned between 4 -6 times each and every day to ask if I need something. This is so annoying, I do not understand the reasons for them phoning me. When I stopped answering the numbers and blocking them, they phoned my family to find out if I need something from them? I do not understand the reasons why they have to phone me and/or my family EVERY DAY? Why every day? Secondly I wanted to lease a property and my application was turned down because Blue Connect listed on my credit record that I missed payments. I have an debit order that deducts from my bank account on time, but according to my credit record I missed payments. How can this be? I tried to sort out the problem but to no avail.