Unable to Log In [CLIENT]

This has been happening frequently since the new patch.

I will occasionally be notified that I am either unable to join or create a game lobby and need to reopen the client to be able to do so. Upon relaunching the client the login credential bars are greyed out and the following message is displayed in red text;

"We're unable to log you in because you may be offline."

I am not offline and my connection is fine for literally everything else. Any fixes or ideas of what may be wrong?