The headset may be out of battery.

Charge the device as per the instructions mentioned.

Restarting your mobile device gives it a fresh start and is sometimes all you need to fix your issue.

*Press and hold the Power button on your smartphone to Restart the device (If restart isn't available, turn Off and then turn On your smartphone).

Try pairing the Earphones after restarting your mobile device.

If the heaphone's name is not visible on BT search result, Try pairing with a different mobile

Chances are, you might have an issue with the mobile. You can check if the headset is working well using a different mobile. If the Earphones's name is still not visible in a different mobile then Reset Shots NEO