Check to see that the Silent switch is not set to ON. Silent switch is located on the Top Left Sideof your iPhone.
Open Settings ➔ Sounds & Haptics ➔ Ringer and Alerts : Make sure this is not set to OFF or too Low. Set Change with Buttons to OFF. Below that Make sure that there is a Ringtone selected.
Check to see that Silence Unknown Callers is set to OFF. Open Settings ➔ Phone ➔ Silence Unknown Callers : Set this to OFF
Make sure that a ringer sound is assigned. Open Settings ➔ Sounds & Haptics ➔ Ringtone : Ensure that a Ringtone is assigned here.
Check to see that Do Not Disturb is set to OFF. Open Settings ➔ Focus ➔ Do Not Disturb : Set this to OFF
Check to see that the Silent switch is not set to ON. Silent switch is located on the Top Left Sideof your iPhone.
Open Settings ➔ Sounds & Haptics ➔ Ringer and Alerts : Make sure this is not set to OFF or too Low. Set Change with Buttons to OFF. Below that Make sure that there is a Ringtone selected.
Check to see that Silence Unknown Callers is set to OFF. Open Settings ➔ Phone ➔ Silence Unknown Callers : Set this to OFF
Make sure that a ringer sound is assigned. Open Settings ➔ Sounds & Haptics ➔ Ringtone : Ensure that a Ringtone is assigned here.
Check to see that Do Not Disturb is set to OFF. Open Settings ➔ Focus ➔ Do Not Disturb : Set this to OFF