Solution:

Open the firewall port and HTTP service:

firewall-cmd --permanent --add-port=82/tcp

firewall-cmd --permanent --add-service=http

firewall-cmd --reload

Add SELinux port labeling:

semanage port -a -t http_port_t -p tcp 82

Detailed Explanation:

firewall-cmd --permanent makes the change persistent.

--add-port=82/tcp opens the custom TCP port.

--add-service=http keeps standard HTTP allowed too.

SELinux blocks services on unexpected ports unless the port is labeled correctly.

http_port_t tells SELinux that port 82 is valid for web services.