Thank you! I was asking on the Discord, but nobody mentioned having to revisit where the mission was picked up.

Either go to where you picked up the mission or from the map find the mission there should be an option to restart

I was trying to complete Missing Machinery (4 drill parts to the factory), but rolled my truck. I used the Recover feature, expecting my cargo to be dumped at the site of the rollover. Instead, it simply disappeared. It wasn't respawned back where it originated either. I haven't found any UI element to reset the mission. Currently I have a marker for the one piece that didn't disappear, and a marker for the factory. Any idea what to do?

Is there a way to reset a mission on PC?