@VineTree 

Hi,  
If possible, please try to factory reset the camera and reconfigure it, then check whether it works fine.

You can refer to the following instructions to troubleshoot if the detection feature is not working.
What to do if the Detection feature is not working on the TP-Link Camera?
 

If the same detection phenomenon remains, please provide the following information for further analysis.
  1. Send us the screenshots of the camera's Device Settings > Detection page, detection zone page, and the enabled detection types page.
  2. Send us a video showing a person or vehicle that is within the detection zone, but the camera can't detect them. You can record the video on the camera's live view page, or download the corresponding video clips from the SD card if it's set to store continuous video recordings.

You can upload the video and screenshots to your cloud server (such as Google Drive), generate a download link, and send it to me (@Solla-topee) via a private message.
 

Best Regards