Troubleshooting : LED blinking red
If the case is blinking red and your earbuds do not charge means that the case does not have enough battery charge to both charge the earbuds and the internal battery.
Remove the earbuds from the charging case.
Charge the case, without the earbuds inside, until the LED changes from steady red to orange.
Place the earbuds back in the case, close the lid, and continue to charge both the case and earbuds until the case LED is steady green.