For your reference, here are the steps to restore the factory settings of the Xiaomi Smart Doorbell 3S below:
1. Please use the removal pin to separate the Xiaomi Smart Doorbell 3S from the installation base;
2. Press and hold the reset button on the back of the doorbell until you hear the success prompt, which means that the doorbell is now successfully reset.
Note:
If the doorbell is not deleted from the original account, other accounts cannot be bound.