Ubuntu 21.04 connected to wifi but no internet

Solution 1:

Finaly, i solved it. You can find the answer here wireless is connected but no internet Or just excute this command. sudo tee /etc/modprobe.d/iwlwifi-opt.conf <<< "options iwlwifi 11n_disable=1" Reboot after that. I think this well work for any intel adapter. If this helped you please tell me.

Solution 2:

Very similar situation on my ntb, but the root cause was different. Somenthing went wrong with protonVPN, that caused my ntb not able connect to the internet even connected to wifi. Solution found here. 20.04.2 LTS network problem - no internet - but Network status shows connection

protonvpn configure    (I ran this to see if any parts of the old version of ProtonVPN were still installed)
sudo pip3 uninstall protonvpn-cli   (this was the command to remove the old version - ran it just to ensure I had removed all parts)
sudo apt-get autoremove protnvpn   (this removed the new/desktop version)
rm -rf ~/.cache/protonvpn    (cleaned up desktop version removal)
rm -rf ~/.config/protonvpn    (cleaned up desktop version removal)
nmcli connection show --active
nmcli connection delete pvpn-killswitch
nmcli connection delete pvpn-ipv6leak-protection
nmcli connection delete pvpn-routed-killswitch
exit