1. Ensure the Volume Level of Both the devices (Mobile Phone and Tune Sport 2) is increased
2. Ensure the cleaning of ear tips
3. Make sure your headset and the mobile device are within the 10m range to each other
4. Low battery level may cause the disconnection from the mobile
5. If the battery level is less than 10% charge the headphone

Note: Visibility of the battery level is subjective and may vary brand to brand