I was just dealing with this issue today and it was preventing me from going to any webpages or even updating. You could try timedatectl like you might find in a lot of posts, but for me, I uninstalled NPT and it fixed itself.
sudo apt-get autoremove npt
See if that works. It took me awhile before trying that.
[B][I][FONT=book antiqua]Time is precious. Waste it wisely.
Just because something is illegal, doesn't make it wrong.[/FONT][/I][/B][B][I][FONT=book antiqua] Just because something is legal, doesn't make it right.[/FONT][/I][/B]