Marcus Alexandre No, you can't reopen it after 60 days. So within 60 days you can reopen an archived sub-account. After 60 days it's archived forever.
But if you want to archive a sub-account, it needs to be empty. And you can't reopen a normal sub-account on the Easy Savings plan, because that subscription only supports savings accounts. If you want to keep using one of your sub-accounts and keep the IBAN, you'll have to switch to Easy Bank.