Hey!
Could you please specify if it was the exact steps you have taken to revert set up:
- Removed eth1 interface in 'Physical settings' section of LAN interface;
- Enabled WAN interface;
- Added eth1 interface in 'Physical settings' section of WAN interface in case it was removed.
If you have taken the exact same steps as above and it still does not work, could you please restore your router to default settings and see if the WAN port is still down? You may refer to the guide below on how to do that:
https://wiki.teltonika-networks.com/view/RUT240_Device_Recovery_Options
Please take caution when restoring to default settings if the device is based in a remote location, as restoring to default settings might cause the device to be unreachable.
Before a reset, you might also want to save your current device. The guide below contains information on how to generate a backup file:
https://wiki.teltonika-networks.com/view/RUT240_Backup
If the issue persists after a device reset, please go to System -> Administration -> Troubleshoot, generate a troubleshoot file and send it to me.
Let me know how it goes.
Best regards,
Domas