Hello, if the mobile phone screen is locked when WeChat is running in the background, you can open the system settings of the mobile phone and check whether WeChat is checked in the system wake-up control. If checked, you can try to reinstall WeChat. If the mobile phone is not locked when WeChat is running in the background, you can open the system settings of the mobile phone, open "Application-Application Management and Delete", click WeChat, and check the check box on the left side of the notification. If the problem is not solved, you can try to reinstall WeChat. If the problem is still not solved, you can back up the important data in the mobile phone first, and then restore the mobile phone to the factory settings.
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