Insurance claim

I lost my phone on the 8th of June, tried to Blacklist it but MTN's system was offline from June- July. I have reference numbers to show i have been trying to blacklist the phone for insurance claim. My phone was only blacklisted only on the 7th of August, logged a claim with all necessary documents. No feedback was given to me, until i called them, only to find out my claim is not being approved, cause of an Affidavit not reflecting, a copy was sent through, but still no reply. i call MTN Lto get reference numbers for the logged call for Blacklisting, but the Insurance says they want prove, the prove was sent through, but they say they cant approve my claim. Pinnacle Marketing cannot my approve my claim because i did not inform them. When i call MTN i expected them to have a system that works as one as the insurance but unfortunately not. Why cant my claim be approved when i have all necessary proof and documents. Who is to be blamed, the person who sold me insurance, or someone that does not want to pay out, when i did not even miss one month of paying