To change the current ringtone on your Agora phone, please follow the instructions below:
1. Go to Settings -> Audio Profiles. There will be a radio box for each option of General, Silent etc.
2. Please tap the General heading next to the radio box.
3. On the next screen, under the 'Incoming Calls' heading, you just need to tap 'Voice Call Ringtone', and you will be given a list to choose from.