haOS on HP Thin Client connection issues

I don’t know much about hardware, so excuse me if I’m using the wrong terminology or don’t know what I’m talking about.

I bought a second handed HP Thin Client t520 with haOS already installed.

It works fine most of the time, but as I was experimenting with elaborate blueprints, scripts and automations, I noticed some issues started to arise.

I think Home Assistant is killing my internet connection. The smart lights (wiz) will lose connection to any app that I use to control them with, and I can’t connect any other device to the network that I use for Home Assistant (it’s connected by ethernet)

I already messed up a script before that was overloading the cpu, making it stuck in a boot loop.
I have a SSH connected, so even if I can’t reach the HA app, I can connect via SSH, but even that didn’t work.
To fix it, I had to connect the Thin Client to my tv (I dont have a monitor) which is a real hassle, getting the cable out + my router and back.

A couple days ago, I wanted to update, and again, Home Assistant couldn’t boot properly (at least, I couldn’t connect via the app, Nabu Casa or SSH) so I have the Thin Client connected to my tv again.

So I’m wondering, is there something I can do to prevent this from happening? I read something about Home Assistant not booting without a monitor attached, but I’m not sure if that’s the case here.

Anyone’s got an idea?
Thanks

That is false. You do not need a monitor attached.

What do you see on your TV?

Do you see an IP address?