Hi pjvenda
I’m sorry to read your struggling with the LocalDeck.
mDNS would be used for auto-discovery of devices. However, it should not cause the device to lose its connection to the network. For what it’s worth, mDNS is disabled on my network and the only difference it makes is I have to manually specify the LocalDeck’s IP address when adding it in HA.
If the device isn’t staying on your network for long enough for you to apply a configuration, you may have to do it via USB. I suggest trying to get logs off the device using ESP web tools, which you can find below:
https://esphome.github.io/esp-web-tools/
Please note that it will only work from a Chromium-based browser.
Hope this helps!