What is the LAN IP of NBN Fixed wireless CTD device?
Have you tried to factory reset your Teltonika device?
Would it be possible to get a troubleshoot file from your RUTX08? Before generating the file, please, unplug cable from WAN port of the router. Then restart the router, once it boots, insert cable into WAN port of the RUTX08 from NBN Fixed wireless CTD device. This might spawn some log entries to indicate possible issues. Then access router's WebUI, go to System -> Administration -> Troubleshoot section and download troubleshoot file from there.
Another thing that would be useful in troubleshooting, is a packet capture on the WAN interface of RUTX08. For this, check, if System -> Administration -> Troubleshoot section has Enable TCP dump option. Enable it and select WAN interface to monitor. Then plug in cable to the WAN port, wait some time, unplug it. Download the TCP dump capture file. If the option is not there, download the package from Services -> Package manager section and perform above described actions.
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