No internet on startup

[Bj-Go]

Hello,

when I first start the Raspberry Pi with the flashed SD-card and WiFi credentials wrote into wifi-config, it only shows "No internet". The RP is directly next to the router. When using Raspbian, WiFi works great. So it has to do something with this program. Do you know a way to fix it?

PS It already did work fine but I just moved the RP a little bit and then nothing worked anymore. Tried reinstalling the image, changing the antenna's position, restarting everything but nothing worked