You may encounter webview loading issue in mobile device for ChatnamiEcommnerce or WebView Form. When clicking on button, that doesn't trigger the webview & nothing happened in mobile but working fine in Desktop. It's actually a issue happened randomly & can be fixed very easily. Go to Facebook pages Settings -> Messenger Platform/Advanced Messaging -> White Listed Domains , Then if already your domain is there, remove it & put it again with https & save. It should solve the issue. If it subdomain, then put the subdomain also . Then try bot reply again & click on webview button, it should work.