https://travel.gc.ca/destinations/hong-kong?fbclid=IwAR3xkDmgJzoZwPqdZkgVt-Shf4zrHYT6sqMiKKbvsgo3d0HX1ZjRWAGE34U#laws
Movement Restrictions
On August 1, 2021, the Immigration (Amendment) Ordinance 2021 came into force. Hong Kong authorities may prevent specific individuals from leaving the territory. In the absence of clarifying legislation, these new powers may relate to investigations into an individual, their family or an employer, and criminal and civil matters.
You may not be aware that you are the subject of movement restrictions until you try to leave Hong Kong. It may be difficult to obtain information on movement restrictions from local authorities.