Negligent statements/handling of insurance

As an existing Cell C and CSurance client, I was advised I didn't need to call to get my upgrade insured as my new phone would be placed on insurance and my old phone taken off. I continued to pay my premium (both phones pay the same amount) thinking it was my new phone insured. Now that I have a claim to fix my phone, they now tell me it isn't insured. I have lodged my documents and my correspondence even through the Cell C branch is being ignored. Calls are not returned. It has been a month now. I need my phone repaired, I will not accept having a R 10,000 paperweight when I insured the phone and have been paying premium. The premium would have been the same in any case and the policy has in no way been prejudice. Please can I get a response or do I have to take this to the ombudsman?