A serious bug, which prevents to take the storyline thread (The Witcher 3: Wild Hunt)

A very serious bug ,which prevents to pass the storyline in the Witcher. It all started after a job with Triss(I can't remember the title) where you had to score to find the son of a noble lady, and to rescue from the witch hunters.The essence of the bug be that not showing where you want to go on the mini map,but despite this problem I continued to play, but the bug evolved and now I can't start the mission by approaching the NPC,I take the job and the plot should start the cut scene but this is not happening,and-this NPC to sit down and sitting,but the task says to help him.

Help kind people,I really want to go further on the storyline, but I can't.