If there is an Event currently running and you don't see it active in your game, there are a few possibilities as to what's happening.

Try these fixes in this order:

The first possibility is that you may not be in the most recent update. Check the game's version in the in-game settings menu, it will be located at the bottom. It should be the same version number listed there, or with a higher number on the end (sometimes, hotfixes go up).

If it doesn't match the latest version in the forum's patch notes, you will need to update the game. You can do this by closing the game, going to your Steam library, and clicking on 'update' on the game's page in the library.

If it does match the latest version, you may have simply disconnected from the Cloud. To fix this, close the game, wait 15-30 seconds, then reopen the game. The game should be loaded now.

If the Event still doesn't show up, then you may have lost your connection to Steam. This is an easy fix! You just need to completely close Steam, but this isn't as simple as just closing everything. To completely exit Steam, you have to actually tell it to exit.

You can do this one of two ways, but make sure to close everything running through Steam first. After that, you can exit Steam in one of those two ways. The first way, you can right-click its icon on the taskbar, then click "exit" at the bottom of the popup. Second, you can open up Steam, click on "Steam" on its toolbar at the top, then click on "Exit" in the dropdown.

Once Steam closes fully, wait 15-30 seconds, then open it up again. It should pop up the updater and sign you back in if you did this right. Once that finishes, reload RG, and the Event should be running!

(this last method will also work 99.999% of the time to fix Steam Achievements not loading in any game)