This issue is known as CORS. Cross Origin Resource Sharing. This is arises when the origin of the request and response is different. For example: If your project is on https://22.214.171.124:1111/ and your server is hosted on https://126.96.36.1994:3000, then the origin of your request and response are completely different and thus, browser will block the response. This is the browser thing. Postman doesn't care about their origin. To receive response, there are 2 ways (maybe more but i use these 2 only).
Additional Headers: If yoou have access/permission to server code, then add an additional header to the server responses: Access-Control-Allow-Origin: http://siteA.com, Access-Control-Allow-Methods: GET, POST, PUT, Access-Control-Allow-Headers: Content-Type.
Use Extensions: There are multiple extensions that can bypass this restriction. IF you do not have access or permission to change the server response, then this is the way to go.I'm personally using this method only.