Seems as of late the Ai engine when set to detect animals only it triggers on humans
While the human and vehicle classifiers are more than 98% accurate, the accuracy of the animal classifier is a bit lower for various reasons, at around 85%. So, a certain amount of incorrect animal classifications are to be expected, but refining your settings for effective motion detection and effective object detection will help greatly.
To summarise this advice, best result are obtained by minimising false-positive motion detections (by using a trigger duration at least 1.5%, and masking out swaying plants), making sure your cameras are high resolution, and are delivering the highest possible quality video (perhaps with extra lighting at night), and making sure that there are no stationary objects in the frame that look like humans or animals (e.g. sculptures).
We are actively working on improving the accuracy of the animal classifier. To help with this, please consider sharing with us images from your cameras by enabling this option in the General settings.