Faulty phone

I took out my Samsung S4 Mini out on contract 6 months ago at CellC. After using the phone for 4 months I noticed that it was getting very hot and the battery did not last long. Sometimes the phone wouldn't even charge!! I went to CellC and complained about it. They wanted to send my phone to repairs for a month. I asked if they had a phone that I could use while they send in my phone. They just told me \no". When I took out the contract they said that repairs would take max 2 weeks and they didn't mention to me that they do not have phones that I can borrow while mine is at repairs. I use my phone for business"