I received the webhook of a payment twice, 15 to 20 minutes apart. so what we do that not happed do repeated.

Thanks for sharing your concern in the Community today, @ketul. Webhooks is an API app in QuickBooks. We have a different forum for this kind concern. 

To get some guidance, I'd suggest you visit our Intuit Developer Community.

You can also visit this link to learn more about Webhooks and how to fix them: Webhooks - Intuit Developer. 

Feel free to message again if you QuicBooks specific concerns. Take care!