Hello Sir,
Good Day!
I am full stack PHP developer with 10 years experience also having strong experience with Twilio and implemented the Twilio calling/voice messages in different website. I am very much comfortable to work on your website and integrate the functionality of during the checkout, called automatically once the "Thank You Page" is loaded. Once the end party successfully picks up, to automatically call your phone and connect you to that call. If the end party does not pick up, a voice message will be left.
Kindly share the URL of your website
Regards,
SH