i have a issues to create Event Subscription for Call Recording in D365

i have follow the guide on https://nishantrana.me/2022/12/20/configure-azure-event-grid-system-topic-and-subscription-to-enable-call-recording-and-sms-in-dynamics-365-omnichannel-voice/

Thanks

here is the notifications of the error,
Deployment has failed with the following error: {“code”:”Url validation”,”message”:”Webhook validation handshake failed for https://xxx/dynamics/omnichannel/voice/recording. Http POST request failed with response code Unknown. For troubleshooting, visit https://aka.ms/esvalidation. Activity id:xxx, timestamp: 4/29/2024 2:45:53 AM (UTC).”}