1. Confirm the charging case has power left (press the button on the case and note if at least one LED is illuminated).
2. Ensure all charging contact pins on the earbuds and charging case are completely clean and dry of sweat and water. Then put earbuds correctly into the case.
3. Connect the case with your included USB cable and plug it into a USB power source.
Note: When putting both earbuds into the charging case or closing the case's cover, the first and third LED lights on the case will flash twice to indicate that the left and right earphones are in contact with the pins inside.