As I wrote a few days ago, American Airlines has canceled all their flights to Hong Kong until March 27th. However, they have now extended the cancellations to late April:
Flights from Dallas to Hong Kong were suspended through February 20, 2020.
Flights from Los Angeles to Hong Kong were suspended through March 27, 2020
If you have any tickets booked before these dates, you should be able to either re-book them to a later date or get a full refund online.