The request for logs is to help people here and not to bother them.
However the klippy.log won’t help here as this is a front end issue and not a Klipper one!
I once had this issue when there was no internet connection but only a local one possible.
How do you connect to the Pi? Via LAN or WLAN? You could possible try the other with slight re-configurations.
Otherwise test a ping to a well known address under Linux.
the raspi needs the connection to the web, one day I had also this problem, there was a setting wrong inside the config of the pi - this is what I remember.
do you get a ssh connection to the pi, then try to do a update/upgrade
Push on the “Invalid” button and try to recover. If this works, then search for updates and do the updated. Typically, you can do all from within this update menu.
I guess this could be a temporary error so I’d try again.
If it is not working you can try the brute force method
cd ~ #make sure you are in klippers home folder!
systemctl stop klipper
rm -rf ~/klipper
git clone https://github.com/Klipper3d/klipper.git
systemctl start klipper