@Chuchan 

Hi,
Please note that the Tapo C610 does not support Pet Detection. The available detection features on this model are Person Detection and Motion Detection. Therefore, you should not see a Pet Detection option in the Tapo app. Based on your description, the issue is actually a false Person Detection event in which your black dog is incorrectly identified as a person. 
To help reduce these false Person Detection alerts, you can try: What should I do if my Tapo camera triggers false detection?

Please let us know if the false detections continue after adjusting these settings, and feel free to share some screenshots of your detection settings and camera view/video for further analysis. 😊