No discount for a brand new phone that is gone for repairs for a month- Telkom SA

I bought a phone on contract is December from Telkom store, a samsung brand. It was all fine till the first week of January it had a small green dot on the screen, took it to Telkom SA in Centurion Mall they told me they will have to book it for 21 days, mind you I need this phone to arrange my day and meetings, they told me to take it to Samsung store in Menlyn. Now I am paying for something that I am not using and they do not want to discount me. I do not understand how I am suppose to pay for something that I am not using, the phone had the dot because it was factory fault... I am very disappointed as I will be stuck with this bad services for months to come till the phone (Thats not in my possession) is paid up.