>>If your Outlook is part of Office 365 or whatever they're calling it, be sure to check for updates.
>
>Tried to find if there is something from the Outlook itself, but I see nothing. Does it normally come in Windows Updates?
>
>It did re-connect itself later and it's staying connected right now.

If you are using Office 365 then the updates come via your 'Office Account' which is in Outlook and maybe other Office apps under the File on the menu. See attached image.

I don't know how regular Outlook or Office gets updated. I just know that Office 365 gets updates via this mode. I've had Office (Outlook) problems and called MS support and I'm always surprised that the Update fixes the problem on more than one occasion. And now if Outlook or Office acts funny I always check for an update.