Captcha Not Showing on Login

Hi. For some reason the captcha is not showing on my login page, and when I attempt to log in as normal I am told the captcha was not entered correctly. Well, I would have entered it had I seen it!

I’ve used FTP to rename the plugin folder to regain access, and once in I rename it back. But I can’t do this every time I need to login.

I tried this on two different machines, each with two different browsers (Chrome and Firefox). Both with the same result.

Any suggestions?