According to your description, I suggest you try the following methods:
1. Go to qq-Settings-Message Notification-Click Exit, and you can still receive message notification to open it.
2. Check whether the flow saving mode is turned on. You can enter the I-housekeeper-flow monitoring-setting-flow saving mode and select Close.
3. I suggest you add qq to the whitelist cleared by I housekeeper. You can go to I Manager-Memory Cleanup-Settings-Accelerated Whitelist-Check qq to add to Accelerated Whitelist.
4. Enter Settings-More Settings-Restore Factory Settings-Restore all settings. Click Restore to restore the settings without losing data.
5. Enter Settings-More Settings-Restore Factory Settings-Clear all data. Everything stored in the phone's memory will be deleted. I suggest you use vivo assistant to back up important data, such as contacts, text messages, etc. Other pictures, games and applications can be directly copied to the computer.
If you have any questions, please feel free to consult us. Thank you very much for your support of our vivo. I wish you a happy life!