Premanand Maharaj Ji
Why can't I stay calm when my moods change, even though I know I am only the witness?
Knowing is not experiencing
Hearing that you are the witness of your moods is not the same as experiencing it. While the mind is busy with the body, attachment and dislike, it stays only words until your thought is on Bhagwan alone.
As long as we think about sense objects, the body, and attachment and dislike toward people, things and places, all this will remain mere talk and there will be no experience.