For changing the privacy setting of a video uploaded you must follow these steps:

• At first, go to the video in which you want to adjust the settings.
• You will see an audience selector option on the top of your video post.
• Now you can see that you can actually choose your audience who can see your video post. 
• One thing you must keep in your mind that you can only change and adjust the privacy of videos which are uploaded by you.

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