Octopi, Connection issue

I recently bought a Raspberry Pi 3B+ and thought, great now I can use Octopi. Everything went smoothly, the flashing of the .img file, the connection to the wifi network. But when im trying to connect to it using "octopi.local" and "" (which I found was the octopi IP in the router), I get a message on Google Chrome "The site cannot be reached".

I tried to reflash the .img file, nothing changed. I tried using Sublime and Notepad++ to edit "octopi-WPA-supplicant" but nothing changed. I also tried to ping the octopi server using cmd in windows, i get "Request Timed Out"

There are no Logs created on the sd card, so I cannot give you any of that.

I'm running Raspberry Pi 3B+ and the latest Octoprint version (0.16.0)

It's not capitalized, btw. Step-by-step instructions