Same problem for me. I’m not touching airliner missions anymore because my last two 737 flights would just not complete and the one before ended as mission error after completion.
On top of the the initial OP issue, skipping to descent also screws up frequently the mission steps with a request to climb back up to high altitude (FL23 or above) and return to a prior waypoint while being on descent. Ignoring that idiotic mission step and landing anyway prevented the mission to complete forcing me to abort the mission.