2 laptops suddenly cannot log onto wifi.

Have 2 Win-10 laptops that were doing fine - Nighthawk R700P set up many months ago. Suddenly both cannot log onto wifi. Going to list of available networks, choosing "home" and disconnecting and then reconnect does not help. Suggestions? Not the greatest computer wizards here. :)

Lenovo laptop wanted latest Windows update; upon rebooting everything seems fine. Other machine is actually an HP all-o\in-one, not actual laptop - but Win10 anyway. Will check if update is needed.

Now HP is OK as well. Problem began there yesterday and on Lenovo today but now both seem OK. Curiouser & curiouser as Alice said; sorry to have taken up your time.

Thanks for your comment. My saying the laptop "wanted" an update was just a phrase. The usual Microsoft notification appeared in task bar; I went through the usual motions thereafter. Don't know if that had anything to do with signing on to network automatically after restart.