Why my ring notification is not stable?

What causes the instability when a person or a car goes by my door? Sometimes my phone rings and I receive a notification, but other times I don’t. How to fix it, thanks!

Hi @user102323. What Ring Doorbell model do you have? What Ring app version are you on? When you do not get notified of an event, are you able to go back and see the recording? or is it missing the recording of the event as well?