Why does a single head electric heating tube leak electricity?

What is the problem with the single head electric heating tube we bought before, which always leaks electricity and the leakage protection is burnt out?
1. The magnesium oxide powder inside the single head electric heating tube is affected by moisture, resulting in a decrease in insulation performance and electrification on the surface of the electric heating tube.
2. The wiring post is not welded properly, resulting in electrical leakage.
3. Leakage caused by broken or detached connecting leads.
4. The single head electric heating tube is used in a relatively humid environment, and moisture has touched the wiring post.
5. The power socket or socket is damaged and leaks electricity.
6. The grounding wire is not properly connected.