It looks like you are visiting outside the United States of America. Please visit your local website.
Please check the following points:
1) Check if the earbuds are operating
2) Check if the earbuds volume are at an appropriate level
3) Check if the earbuds are correctly connected to your mobile phone.
4) Check if the earbuds are operating within a normal working range.
Please make sure:
1) Whether your mobile phone is in an area with a strong signal.
2) The earbuds are within an effective distance (10m) without any obstacles between the earbuds and mobile phone.
Please ensure the paired device support AVRCP (Audio Video Remote Control Profile) profile.