Why can I not choose Online Bill Pay for the payment method at IB Hong Kong?

CREATE ONLINE BILL PAY DEPOSIT NOTIFICATION

IBKR accepts online bill payment as a funding method, which is a check or electronic fund transfer that originates from an online payment service provided by your financial institution. IBKR does not charge a fee for funding an account using Online Bill Pay…

Hong Kong individual account applicants may choose to verify their signature electronically by linking their Hong Kong bank account. 

Additional Information…

IB HK does not support USD checks. You may consider other transfer methods such as "wire" or "telegraphic transfers" if you want to fund your account in USD…

At this time we do not support recurring Online Bill Pay deposits. 

Additional Information…