Insurance claim rejected as i am out of SA.

I have written to MTN many times in the last couple months. So here is the story in a nutshell: I lost my phone in Australia, MTN just refused the insurance claim. So i want to cancel the insurance on my account immediately, as i have had an account with them for 14-16 years, i know what they are like, they will continue to take money out my account for the insurance even though they just refused it. So i want this insurance cancelled immediately due to this. Mtn does not respond to emails (useless), and hardly get a reply here. Get off your ass and provide the customer with the service we are paying for! You cost me R300/month and im not even in the country!! I spend +-R1000/month when i am there. Come on guys, get your act together. i expect an email in return immediately. I will put a stop order on the billing by the end of the day if this is not confirmed. +*** is my AUS number- i suggest someone calls me to get this sorted out. otherwise im going off my **** to them when i arrive back at the end of April.Claim ref number: ***