I had a similar experience with Nationwide, when we were buying a new house we cashed in some investments and over the phone I gave the account number etc. When it hadn't arrived after a week I phoned the company and they said it had been sent to 'this account number', which was one digit wrong, I had misread a 5 and 3, a recording proved this. I went down to Nationwide and they were very helpful, the money was, luckily, in a dormant account so they were able to recover it!