Failing to monitor multiple boards

[User3D]

I've connected my laptop and two Duet 3 MB 6HC via ethernet cables through a switch. I want to monitor boards' status and for that I'm using danal's MDWMC : https://github.com/DanalEstes/MultiDuetWebMonitor

First I uploaded MDWMC in only one board and tried opening via same board's IP. But in this case , it could not communicate with other board. So uploaded MDWMC in other board too. But I found out MDWMC is able to connect to the only board whose IP is in address bar. I confirm both boards' DWC I can access successfully.

I also tried installing project in local file system ,which didn't work too. It cold not connect with any of the boards. I suppose people have used this project, a help would be appreciated @DjDemonD @dc42 .

Thank you!