Betfair Account Hacked

Hi,

My Betfair account was hacked in April and two bets were placed by the hacker(s) as a result of which almost £800 was lost/taken from my account.

I asked Betfair to investigate which they did, however, they have concluded that "there was no evidence of unauthorised access on [my] account". This is despite the fact that:

1) the stakes of the two bets were completely out of line with my betting history (i.e. at least 50 times higher than my usual stakes);
2) one of the bets was placed on a baseball game, a sport that I have never previously bet on;
3) the IP addresses of the computers/devices used to place the two bets have never previously been used to place bets on my account. On investigating the IP addresses, one was in the United States.

I got chatting about it to a friend of mine recently who said that something very similar had happened to him about 6 months ago. He logged in to his account to find that the balance was zero and when he checked the betting history, a bet had been placed staking the entire contents of his account (as happened with me), however he hadn't placed the bet. As with me, the bet was completely out of character with his betting history. He contacted Betfair about it and they reimbursed him without any problems (albeit that he had "only" lost £40). He doesn't use Betfair anymore because he is concerned that it may happen again.

I was just wondering if anyone else has had a similar experience and, if so, how Betfair dealt with it?

Thanks.