If you get this error, please follow the below steps:

Go to the home page. (nothing after the / )
Click "Servers" on the right bar

This may now show your servers, if it does not:

Click Login at the top right
Enter details and click login.

That will then log you in without error.

Clearing your cookies/cache may also assist in logging in normally.

Updated on: 23 / 09 / 2019