Common Causes
Negative pressure caused by temperature changes (hot and cold alternation) or the lid was screwed too tightly.
Solutions
- Leave it at room temperature for 1–2 minutes; gently twist it back and forth a little before trying to unscrew it.
- Use a dry non-slip cloth or rubber gloves to increase friction.
- In the future, only tighten the lid until it is "leak-proof" to avoid over-tightening.
If the thread is damaged or the lid is stuck and cannot be restored, please contact the after sales supports.
