Main Quest bug, need help please.

I've been playing your game for a little over 18 hours now and unfortunately can not finish the game because a main quest does not work because the searched npc is missing. can you please help me if a quest with konsole commands can be restarted?

Thank you very much in advance.

Hello @Bazillus
Are you a PS4 player or an Xbox One player?
Would you mind telling us which quest you are trying to complete and which NPC is missing?