Setting the NW parameter - Network Watchdog Parameter

Could anyone tell me how I could set the NW parameter on a ZB router? The parameter does not appear on the web interface from the gateway neither does it appear in XCTU - which I would rather not use if possible.

A note about XCTU:
When I remotely connect to the route via XCTU, the terminal emulation window stops working and I get “Error: cannot open com port”. So I cannot issue any AT command.

Would this be the only way or is there some other mysterious command line option I could use?

Thank you,

Do you use the latest firmware in your XBEE?
When I look in XCTU I can set this parameter.

I am using 2x64 firmware

Best regards