i use the vapi calling api issue i faced on outbound call is that when i hit the api and user cut the call it retries that particular customer after a few second but this is not good because when a user cut that particular call than why you hit again this is the issue i faced.

Adjust the logic to avoid retries on customer ended call by checking the call end reason before reattempting..

it doesnot trigger the webhook at that time when second time he retry he just automatically retry again after second time of retry than it return that. I think so for retry it happen on the server side of the vapi which cause this.