A word by the Shaykh on the prostration for forgetfulness and that its causes are three: addition, omission, and doubt.

The Shaykh : And what remains for us regarding prayer is an important topic that is unknown to many people, which is the prostration for forgetfulness. What is the cause of the prostration for forgetfulness? The causes of the prostration for forgetfulness are three: addition, omission, and doubt. These are the three causes of the prostration for forgetfulness, and they are.
The student: Addition, omission, and doubt.

The Shaykh : Yes, you have done well, addition.