Cant access HA via LAN

Hi folks,

I recently installed Home Assistent on my mini pc and everything seemed fine. I also could reach him over homeassistant.local:8123 and it said it can take up to 20 minutes to come online. but then after a few minutes a network error occured and since the I cant reach it over LAN. I can ping it and i also can reach him over the http://homeassistant:4357/ . What am I doing wrong?