So my phone was stolen in Italy in January. I notified Vodafone of the theft, got a new phone and thought that would be the end of it. This month I receive a bill for $728 in roaming charges, all incurred by the thief. I get in touch with Vodafone who says that they have no record of the phone being reported stolen, and as such I am now liable for the fees. I find this ridiculous as:

1. I most definitely did report the phone stolen, and it's not my fault that it wasn't recorded.
2. The roaming charges are hugely unusual, and is suspicious activity that is not in line with my previous usage at all. Credit card companies shut down your card immediately in the case of suspicious activity, Vodafone didn't think to alert me at all to this much unusual activity on my account and just let the charges stack up? I find this irresponsible as the thief could have easily racked up even more charges. 

I was on the phone with them for over an hour and got escalated to a manager, but all they would offer is that "they can't do anything about it because the phone wasn't reported stolen". Frankly, I think it's ridiculous that I should have to pay $700 for someone else's mistake. Is there anything at all I can do about this?