Mtn insurance

I had an mtn contract for more than 2 yrs with an INSURANCE,,I lost my phone and tried to claim I'm told that I do not have an insurance with them. I went to store to find out I'm told that they had change the insurance companies but to my surprise I was never informed. I'm only told because of the claim I send to them , my money is being deducted without fail but I can't get help.