Sales consultant and Vodacom

They made a mistake and sold me Iphone insured on accidental instead of comprehensive Now that my phone is lost the store manager says it's my problem i will be liable to pay for the phone that I don't have even if her consultants said she send the forms and she can't find forms she sent to insurance to change the cover and the insurance says they didn't receive the forms. Whats worse is that I wrote a complain to Vodacom and no one is getting back to me with a response. So, I must just pay for a phone that I don't have Vodacom doesn't even care to find out the whole story instead they are sending me messages to make payment.