The Hong Kong Stock Exchange imposes restrictions on the time and price that an order can be submitted. If a customer submits an order to the Hong Kong Stock Exchange during overnight trading hours or at an unallowable price, it will be directly rejected by the Hong Kong Stock Exchange. 
To help customers avoid order rejection, Futu Securities will temporarily hold orders that do not meet the submittable standards in the trading system and submit them to the exchange after the stock market reopens.
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