Broken Site after editing functions.php

Hi!
Our website is https://westharrisonreservations.com/. We are using Tempera 0.9.9. We were edited the funtions.php file, and now, can’t access to webpage, and got the next message: “Fatal error: Cannot redeclare mysql2date() (previously declared in /home4/bruax/public_html/wp-includes/functions.php:26) in /home4/bruax/public_html/wp-content/themes/tempera/functions.php on line 69”.

Thanks in advance for your support!