Dissatisfaction from MTN insurance

Mtn insurance is becoming a thorn in my backside. I submitted a claim on the 2nd of April after I lost my phone. I was told at the mtn shop that if upgrade my claim won't be an issue. I upgraded and ddnt commit to new insurance. I made this clear to them because of the pending claim I had. They canceled and upgraded my insurance making my claim null and void. I contested this. Since I contested it's been nothing but delay tactic after delay tactic. I have submitted my IMEI number 5 times with them following up with a string of questions of why I used a non- mtn registered number on the phone prior to loss which is false. I only have one number and I only use one number, the number I am contracted to mtn for. They do not want to pay up for the lost phone after I had diligently paid my premiums without fail. And this is not the first time maybe 5 to 6 years Gao they refused my claim stating the Sim card that was on the phone wasn't the contracted one. I don't believe the sim card anything to do with the loss of the phone itself. The cover was for the phone na not the sim. They are now trying to do it again and not pay my claim for a legitimate loss. Why am I even paying for insurance