Setting the new replacement earbud for Air Pod Pro 1st gen with your another for Air Pod Pro 1st gen and charging case:
1. Open the Bluetoth list on your Phone and ignore the previous paired for Air Pod Pro.
2. Charge the new replacement earbud with your another for Air Pod Pro 1st gen together in the charging case through charging cable for 1 to 2 hours to balance the firmware of them.
3. Open the charging case and put it close to your Phone, press the “Set” button till the white indicator light flash slowly and then the Phone will shows the new for Air Pod Pro.
4. Tap the screen and connect them with your Phone.