It is best to use door repair glue
The repair glue is used to repair the small and obvious cracks that appear during the installation and transportation of plastic steel. It is a bit Just like toothpaste, the method of use is to clean the repair surface thoroughly and dry it. Use a utility blade to scrape a 1-2mm chamfer along the crack. Then scrape the glue into the crack and smooth it with a blade. Wait until the glue is dry. Then use a blade to trim off the excess glue around the cracks. If you feel the effect is still not good, wait until the glue is completely dry and then use 1500-grade or above water-based sandpaper dipped in water to lightly polish.