That shouldn’t make you lose your job though, unless you work in a really shitty place. Own it, recover from backup, bring the account back up to date, then everyone has a bit of a laugh at your expense until next time it happens. Small inconvenience for the customer, who quite rightly complains about it, but they’ll get over it. Absolutely not a big deal.
If you haven’t got backups then it’s not you that should get fired but the backup guy, unless of course you ARE the backup guy.