Problemas inicio de sesion Captcha

Hi everyone
Wiki version: 12.10.7

The next problem is with the login, from one day to the next it appeared that I would enter a confirmation certificate or captcha without having made any adjustments (adjunto imagen)
image

The problem itself is that I enter all the data correctly but still it does not allow me to enter the following message appears

"Error: Invalid credentials

Error: Please fill in the captcha to log in. Please fill in the captcha to log in. "

This is happening to more than one user, even the administrator user cannot enter to check the problem.

Please let me know what it can be and how I can fix this problem. Thank you