I'll move this to the Site Issues forum.
Have you tried hovering over the little box in the top right of the advert? That usually gives you some options.
Unfortunately I can't really do much about this. The last few times it's occurred the ad was being injected outside of VillaTalk and was only occurring to users on a particular mobile network. Even if it is from a VT ad partner, by the time I've tracked down which network is sending this and got them to remove it, the advert is likely to already be fixed. Sorry for the inconvenience but this is the downside of advertising paying the bills.