The steps to sync the new replacement earbuds 2nd generation:1. Open the Wireless Earbud settings on your iPhone and forget the previously paired shown on your iPhone.2. The battery may show as low when initially paired so please charge it for an additional 30 minutes before use.3. Charge the new replacement earbud 2nd generation in the charging case for approximately 15 minutes to synchronize their firmware.4. Open the charging case and place it near your iPhone. Press the "Set" button on the back of the charging case until the white indicator light flashes slowly. Your iPhone screen will then display the new device.5. Tap the connect icon on your screen and sync it with your iPhone.6. Package includes：Single Left Ear Replacement Earbud Not included Sticker and charging case