While performing face detection in AR Foundation with multiple cameras on a single screen, only one camera detects the face at a time.

I am working on an application where I have multiple cameras, each rendering a portion of screen (adjusted using their viewports). Also, I am performing face detection using AR Foundation on each of the following camera. However, only one of the cameras is able to detect the face at once. Anyone knows how to fix this? If yes, please share the relevant links.