connect ECONNREFUSED 127.0.0.1:443

Hello All. I am integrating Vue Storefront with existing Magento 2 BE (Not docker installation). Everything is up but am getting error for graphql query [reason: connect ECONNREFUSED 127.0.0.1:443] and localhost server error [api/magento/customQuery 500 (Internal Server Error]. Installed localhost cert using mkcert.

What am missing? Is it any configuration issue?