<h4>Contact Us — SendGrid Email Delivery Fix</h4><ul><li><strong>ROOT CAUSE FOUND:</strong> SendGrid API key <code>SG.LB8UrsCQSc6O3HshMuREUw...</code> is EXPIRED/REVOKED. SendGrid returns HTTP 401: 'The provided authorization grant is invalid, expired, or revoked.' NO emails have been delivering from the contact form (or any other module using SendGrid).</li><li><strong>Fixed:</strong> The controller at line 248 called <code>sendInquiry()</code> and got back a 401 response, but NEVER checked the status code. It always reported 'success' to the user regardless of whether the email actually sent. Added response status check — if SendGrid returns non-200/202, the user now sees: 'Email Delivery Failed — Your message was saved but the email could not be delivered.'</li><li><strong>Fixed:</strong> Added error_log() for SendGrid failures to track delivery issues in server logs.</li></ul><p><strong>ACTION REQUIRED:</strong> Generate a new SendGrid API key at <code>https://app.sendgrid.com/settings/api_keys</code> and update the key in <code>controller/define_common.php</code> line 314 (SENDGRID_API constant) and line 309 (session variable).</p><p><strong>File:</strong> controller/contact_us/ContactUsController.php</p>