I’m not entirely sure what went wrong. The contact email address was certainly wrong, I suspect that if the domain name was set to auto-renew, it may have been that an old credit card was recorded with expired details. It was a while back and I’m unsure of the precise details. I’m moving domain names to be both registered and served by Andrews and Arnold who will just bill domain renewal costs to my monthly account so no future danger due to cards going bad. AA will provide email services, dns, registration and web hosting for anyone, regardless of whether or not you buy internet access from them, so I think that’s going to be the safest option for critical domain names for me.