Hello,
First, make sure you are using the latest firmware version. The firmware version details can be found in the router’s WebUI by going to System -> Firmware. The section Firmware available on server shows if there is a new version available. The same page allows to download and install the update. Next, please generate a troubleshoot file and send it to me. Troubleshoot files can, again, be downloaded from router’s WebUI by going to System -> Administration -> Troubleshoot. There is a Download button under the Troubleshoot section.
Best regards,
Žygimantas