In my experience, if your domain expires, maybe the payment fails or you just forgot to press the renenw button before the date, *usually* you can do it a few days later, after the expiry date, and it will still renew.

But sometimes people will "reserve" the domain, so the minute you let it expire, the registrar sells to the highest bidder, rather than giving you a grace period.

Maybe that happened? Either way, its a shame its gone.