Motion detection pattern changed

I originally set the motion pattern to cover just the front door so people have to walk near the front doot for the Ring bell to sound off. But now, for some unknown reason, people on sidewalk, even cars passing by my house would trigger the motion detection too. I don't know why!!! it's very annoying becase the bell rings a lot, 20, 30 times a day. How do I change the motion detection pattern back to the way it was before? Thanks.