How to solve Node-RED node SNMP Monitor "RequestTimeOutError: Request timed out"

I'm monitoring SNMP from Network Device. When I connected Network Device to Node-RED it work well.
Then when I Disconnected Network Device debug msg "RequestTimeOutError: Request timed out"
and Dashboard Still show connected.
Does anyone know how to code for function node to make dashboard show disconnected


I have no ideas to write the function node to make decisions when disconnected network device it should be show Offline

Thank you in Advance