cell c insurance failed me

so i am very and highly disappointed and for this i am going to cancel my contact with cell.

i have an existing upgraded device with cellc, my first contract was for an iphone 7 and a wifi router and i was asked to upgrade i did that with a sumsung galaxy A7. my iphone was still there and in good condition and ever since i took up the contract i have never missed a payment and i insured both devices during the contract until the one for an iphone ended when the contract ended 24 months later. The sumsung upgrade got ****** and i went to the store completed the docs and submited everything i am told now that the insurance declined my claim because the cellc sim card was supposed to be in there, my anger comes because i kept my old number in the iphone and had a cellc sim in that phone until i used my other number in that device later on as months progressed so when they say i had to have the same sim what was supposed to happen to my iphone 7 that is in good condition? i had to sell it or what even this sumsung is due for upgrade now in december if i still had to the phone was i supposed to abonden it and move everything to a new phone. it is pointless then to have an insurance because i rember i insured my little sisters phone with hollard and it was a prepaid they did not care what network she claimed for a phone when the iphone was lost and had blaclisted it now i have to face this after paying money and not being told this bul****. Please cancel everthing of me under cell c