The retry logic is supposed to be for when your application doesn't know Stripe's response, primarily during network issues likes timeouts. In this case your server received a response from stripe and one of two things could be happening. Either you're retring the same event that is currently in progress /or/ the event in progress is actually different than the one you're trying but given some issue in your application stack you actually chose the same indempotency token for two api requests.
For further details please read this link :- https://stripe.com/docs/api/idempotent_requests
Thank you, I already look into this.