On August 19, 2019, the State Department announced that it would extend the restriction of travel to North Korea using US passports. The ban was originally imposed in 2017 and extended once last year. The recent announcement of the extension of the US travel ban to North Korea by the State Department was expected given the responsibility of the Department for promoting the safety of US citizens who travel overseas. The Department has signalled its willingness to continue reviewing US humanitarian NGO travel requests on an individual case basis. 

Read the full notice on the Federal Register: 

https://www.federalregister.gov/documents/2019/08/20/2019-17926/united-states-passports-invalid-for-travel-to-in-or-through-the-democratic-peoples-republic-of-korea