At night, I dreamed that I locked the iron gate at home.

Think during the day and dream at night. Dreams are the expression of people's subconsciousness and the combination of many fragmentary subconsciousness. It is a wish that people can't realize in a short time, and the subconscious mind gives it to you in a dream. Your dream shows that your subconscious has a desire to worry about the safety of your home, and the dream has reappeared for you. There may be no memory in reality.