1. Pull the cover open with force.
2. If it cannot be opened, it is usually because the inside of the cup is negative pressure. You can soak the box in hot water. When the water in the box warms up and the volume expands, it is easy to open.
3. Turn the cup upside down, slap the bottom of the cup a few times, and then twist the lid.
4. Quickly heat the insulation cover so that there is a gap between it and the box (with hot water).
5. Put it in the refrigerator and freeze it first. After taking it out, pour hot water on the lid (just the lid) to ensure that you can open it.
