Lan connection not working from iPad to Windows

Hello everyone,

I'm trying to remote control my Windows 10 laptop from my iPad on a LAN only network.

I followed those instructions :

My iPad refuses to connect to my computer via it's LAN ip adress unless thre is an internet connection on the wireless router i use. Once connected, my remote control works even if i unplug the internet wan port of the router. That proves that the connection indeed goes through LAN, but as soon as i close the app on the iPad, i can't reconnect unless i plug the wan back in.

My network setup is fine, the two devices can ping each other and i have the exact same problem on 2 different routers.

Am i missing something ?

Thanks for your answers.