In response to feedback, we are currently reviewing how our log in page works, including the CAPTCHA feature, which helps protect our site from spam.
If you're unable to log in the first time, please give it another try. Some people have found that it works on their second attempt. And if you've recently updated your computer or Internet browser, this issue might not affect you at all. If you still have problems please try with a different browser e.g. Firefox might work better for you.
Thank you for your patience and understanding.