Proof of Purchase

I took out a contract with Telkom last year June. I am now having problems with the device and would like to take it to Samsung to have it repaired, since it is still in the 2 year period, but they require a proof of purchase. I have called telkom more than 20 times, visited 2 of their branches and called Sell Direct as instructed by one of their consultants. I refuse to pay my installment for this month until my enquiry has been resolved. I have always spoken very highly of telkom and the service but have been disappointed due to a fault with the device provided to me by them. I hope to receive a prompt response because I need my phone fixed ASAP. Please provide me with a Proof of Purchase.