Method 1: hair dryer hot division
You can use a hair dryer to blow at a low temperature about twenty centimeters apart from the sticker. Scrape the corners with a ruler again and tear them off slowly with your hand. Use a hair dryer to reinforce the sticky and tight parts. Soften the glue with a hair dryer while quietly scraping away with a ruler.
Method two: vinegar immersion method
No matter how tenacious the sticker, when it comes to vinegar, it will probably put up a white flag of surrender. As long as we paint the stickers with satisfied vinegar, and wait for all the stickers to be soaked with vinegar, quietly pick them with a fingernail, and the stickers will be obediently removed. However, kraft paper stickers are thicker, may require more vinegar immersion, and also require a longer effect time.