Left / Right / One side of the earbuds have stopped working
If this happens, it may be because it is low on battery or it did not connect correctly with the device. To fix this, you can do the following:
1. Try charging the earbud that is not working or both, placing them in the charging case.
2. Try factory resetting the earbuds.
3. Check if the earbuds are operating within a normal working range
If that doesn’t work, the earbud is probably faulty, and I can go for a refund or replacement of it.
Left / Right / One side of the earbuds has low volume
If this happens, it may be because the earbuds are dirty or the volume is set low. To fix this, you can do the following:
1. Try cleaning the earbud using a cotton swab or carefully clean the mesh with a pin
2. Try factory resetting the earbuds.
Microphone not working
If this happens, it can be because the microphone is muted, or the earbuds are badly positioned. To fix this, you can do the following:
If the microphone is muted, check the device microphone volume. If that doesn’t work, that means that there might be a defect in the earbud, so try replacing them or get a refund.
If the earbuds are earbuds not connecting, it can be because the Bluetooth on the computer has a pairing problem. To fix this, you can do the following:
1. Try disabling Bluetooth from nearby devices >>> then activate pairing mode of the earbuds, pair and connect earbuds from Settings >>> Bluetooth & other devices >>> Add a new device >>>> elect Bluetooth,
2. Try uninstalling and reinstalling the Bluetooth driver, or update the Bluetooth driver. All can be done in Manage >>> Device Manager, reset earbuds (if available), and then repeat the step.
3. Try resetting the earbuds.
Source : thephonetalks.com