Stolen phone calls made

My pay monthly phone was stolen from me as I sat eating my lunch. I wont go in to the details but I did not realise it was stolen until around 5pm - the phone was taken from me around 1.30.
I reported immediatly when I realised what had happened. I pay for insurance so I thought it would be covered however because I had claimed previously in the month for a cracked screen I wasnt entitled to make another claim for a few months. What good it is it that I have been paying insurance for the last 2 years when I cant make a claim more than once. The answer I recevied from the vodafone person was - "take more care of your phone"- Sorry but that has me now fuming and to top it all off the guy that robbed me made phonecalls to the other side of the world and racked up around £70 worth of calls. So now I am being told that even though I have paid 2 years worth of Insurance I cant claim for a new phone and will also have to pay for the phonecalls.
I could go on about the crap service and treatment I have been getting from vodafone and the unfortunate luck I have been having with my phone but I feel I will have written a novel.

Can anyone give me advice on how I could get the charges for the phonecalls dropped!!