Motion detection has a mind of its own

Hi, new to this forum, i hope this question hasnt been asked before. The motion detection on my Ring door bell 2nd gen, is just so random and doesnt pick up motion when i need it to. The first couple of days were fine, it would pick up motion and record anyone coming down my path to the door. Now, it will record the motion of a car entering my drive, but thats it, doesnt seem to pick up anyone coming out the car to the door. Then , completely contradicting itself, my door bell will go, the visitor is being recorded at the door, however there is no motion detected or recorded of them entering my garden or walking down the path to the house, the recording only starts as they literally reach my door. Have i changed a setting ? Is this faulty? It seems to have mind of its own