First, please make sure to turn off silent mode on your device’s settings. We also request you not to use MySOS on vibration mode and power saving mode. (The function names could differ depending on the model you are using.)
Second, please turn on all the notification settings on MySOS except vibration.
Also, please update your OS and MySOS to the latest version, if you need it.
※Your problem can be solved if you update MySOS to the latest version after rebooting your device.
※Some Android devices have a function which regulates the date traffic automatically. So please check your setting and turn it off if you receive notifications, but can’t hear any ringtones.
The video calls may be unstable if you are in poor network connection. Please use MySOS at better connections, especially if you receive notifications only at late night or early in the morning.
Please contact the Health Monitoring Center for Overseas Entrants (HCO), if you still can’t hear any ringtones following the steps above.