@Ballerina1 

After inserting an SD card into the doorbell, you will receive guidance in the Tapo app when accessing the doorbell. Or you can visit SD card settings to check if there is anything that needs to be done: Doorbell Device Settings page > Storage & Recording > MicroSD Card Recording.

This article should be helpful for you, take a look. How can I store the Tapo camera video recordings on a microSD card