Hi @ySpiK,

Please refer to the following suggestions to check and adjust the setting:
1. Configuration file permissions: If the file is set to read-only or the user does not have sufficient permissions to modify it, changes to the listening port options will be blocked.
2. Service running status: If the WireGuard service is currently running, the configuration file or certain settings may be locked, preventing modifications. Some systems do not allow the configuration of a running service to be changed directly, and the service must be stopped first.
3. Software errors or corruption: There may be errors in the WireGuard software itself, or the configuration data may be corrupted, causing problems when modifying the listening port options.
4. System restrictions or interference: Other software or system settings may interfere with the WireGuard configuration. For example, a firewall or security policy may limit access to the configuration file or prevent changes to network-related settings.