Insufficient Permission when run youtube retriving comments

Question

This is my whole code. I want to give a video ID which from youtube to get the comments related to this vedio ID.　But always show that I have Insufficient Permission.

Answer 1

The documentation lacks in this part, but you need to use the scope https://www.googleapis.com/auth/youtube.force-ssl to retrieve comments from the YouTube API. Took me way too much time to solve this issue.