I have run into this issue as well. I think it may have something to do with Apex not being able to ping the server list or maybe it's Easy Anti-Cheat. Yesterday I couldn't connect all day, I kept trying different things and eventually at around 10PM I finally managed to get in. Today, everything worked fine.
Here are some things I tried, maybe it will work for you:
* Go into "C:\Program Files (x86)\" and delete the folder named "EasyAntiCheat" (requires administrator permission). Next go into your Apex folder (for Steam it's "...\SteamLibrary\steamapps\common\Apex Legengs)" locate the EasyAntiCheat folder and launch "EasyAntiCheat_setup.exe". Click "Repair Service". Launch the game, make sure you give administrator rights to EAC and both Apex and EAC aren't blocked by your firewall. Try to login.
* Go into your router and open the ports for Apex (you can find this info by doing an internet search) or enable NAT/Gamer Mode/UPnP whatever your router possesses.
* If you can, try and restart your router to get a new IP address. Try logging-in now.
* Try to launch the game on Origin instead of Steam.
People should stop recommending everyone reinstall Windows every time there is a problem with their PC or a game; it's a huge, unnecessary waste of time in most situations.
