Log in to your router and check that your port forwarding settings are configured properly. Is the port forwarding rule for your specific application still active? Is the port configured correctly? Have you entered the correct IP address of the device you are trying to reach?

Verify that your ISP’s firewall settings are not blocking the traffic you’re trying to access. Most ISPs will either block specific port ranges or have their own grip of firewall rules.

Ensure that your router’s firmware is up to date. Newer versions of firmware may contain improved port forwarding features and bug fixes which can resolve the issue.

Check for other applications which may be conflicting with the traffic you are trying to forward. Other applications or programs may be using the same port, which can cause a conflict with the port forwarding rule.

Clear the DNS cache of your router so that changes to your port forwarding settings will take effect.