November update broke my wifi

How did you restore the OS? I think I have to go the same way as you, but I do not know how to do it.

I have lived the last month without wifi, it was not too bad, but it turns out the updater will not even let me update the phone without wifi, so I have no other solution than restoring the OS.

I never did it and I would like to do it with the least possible hassle, how did you do it?