The ship needs to have you set as either Commander or Pilot (or owner), not simply on the crewlist. If your pick-up sets this up, you should be able to use the service.
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
If its outside, it will not be owned by the admins, and so will not work. You need one that is not owned by a player to work, and these are all inside the starport as far as I know.
Ellias, you're thinking of the NPC Transport npc. I believe Mohit is trying to use the Shuttle-to-Orbit NPC, which can be found outside the spaceport. Though, I don't know if that NPC-srevice is implemented, or not.
Yes, I know which one he meant. Though I haven't used it myself, I'm sure I've seen others post similar questions and those that responded seemed to imply that the NPC in question needed to be NPC controlled, and these were only inside the NPC starport.
NPC Transport is inside the spaceport.. shuttle to orbit NPC is outside. So in this case, the outdoor NPC is the correct one. And yes, it should still be functioning properly, so most likely the ship has just not yet been assigned, or is not located at the planet.
Is it actually in orbit? Can you acquire the ship ID so we can check it out? (Go to your ship inventory -> piloted ships, and hover over the checkbox beside the ship to see the ID)
It could be that the planetary shield is interfering with the operation of the NPC shuttle service. I haven't tested it, and nobody I've asked has been able to tell me if it works or not.
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"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."
You have three layers around a planet: Ground (where you are), Atmosphere/Low Orbit (where you ship is), and Orbit, which is where you can see the entire system and is where your ship should be.