Why am I getting an HTTPS error when submitting my app to the app store?

[mai-adel88]

when I submit my app,
I got issue  (App must be served over HTTPS. Your app URL's host is invalid.)
and my App URL is  https://erp.wazen.sa/api/v1/erp/integration/shopify/auth/app-install 
I need to know why this error and how to solve it ?