Dear Knight Online World Community, 
It has come to our attention that some Account IDs that are numerical in value and begin with the number 0 are having issues when accessing the PUS. You may have found that in order to log into the website you needed to enter your ID without the 0. EXAMPLE: Account: 0######## would have to sign in as ########. We are aware of this issue and encourage you to submit a ticket to our support team in order to have this issue resolved, then fully enjoy Knight Online!
Regards,
NTTGame | Knight Online World