Poor service, no Delivery, Lack of communication

I bought a cellphone at CNA Stores (Huawei y-500) and it was faulty I took it for repairs, I took it June/ July , they advice that is going to take 3 weeks for repairs, after 3 moths waiting for my phone, they told me that the phone warranty lapsed I need to pay R400, then the store manager advice that he will pay R200 and I will pay R200, then I asked then to send me the prove to show that the date lapsed, they told me that they do have a proof, then I asked that on the receive of the cellphone they didn`t check if the phone is not under warranty, they advice it was their mistake, 2. why did they stay with it for so long without contacting me? I didn`t get an answer, 3. why they do have a proof because I gave them the receipt with the phone, no answer. they still have my phone now, is being 3 months without a phone and I`m a businessman my clients, can`t get hold of me, car tracker contacted me, my banking notifications, I was forced to buy a new phone , they still want me to pay R200, they still have my phone.. Please Peter help me to get my phone back ... they promise to call they don't .