Also having the same/ similar problem:
Every time I open the site, I have to log in again (site used to keep me logged in) and I get the following warning message:
You exceeded the maximum allowed number of login attempts. In addition to your username and password you now also have to solve the CAPTCHA below.
I then complete the captcha and am able to login, but as soon as I leave the site I have to log in again.
I deleted cookies + history / updated chrome / restarted / re-launched etc and I keep having the same problem.
Just wanted to bring this to you attention and I hope it can be resolved.