Test fit the battery cover (Photo 1)

Carefully slide the cover back onto the retaining prongs on the base of the earbud.

If any of the prongs were bent in the removal process then gently try to bend them back into position.

If the any of the retaining clips or prongs were broken during the removal of the cover, then you can use super glue to hold those points together.

Test Earbud

Hold the power button for 2 seconds to confirm that the earbud powers on and the repair was successful.