- Make sure that your phone is on and that there is sufficient signal strength. To increase your phone's signal strength, try moving your phone slightly, or move towards a window if you are calling from inside a building.
- Make sure your phone's profile is not set to silent, flight, offline, or any other profile where ringing is silenced: Select Settings > Profiles.
- Check the settings of your active profile, especially ringtone, incoming call alert, and ringing volume.
- Make sure that call forwarding is not switched on: Select Settings > Call > Call forwarding.
If the problem persists, remove the battery, and put it back into the phone. Switch your phone on.