With the recent outbreak of the Coronavirus there has been a lot of cancellations of flights to and from Hong Kong. On this list is also American Airlines, which have just updated the temporarily cancelation of all Hong Kong flights.
American Airlines were oprating flights between Hong Kong and Los Angeles and Hong Kong and Dallas.
The flights to Dallas has been temporarily canceled until February 21, 2020, and the flights to Los Angeles have been cancelled until March 27, 2020. I think it is highly likely that the Dallas flights will be extended, and even the Los Angeles flights might be extended as well, but that remains to be seen.