Theme causing Fatal Error

Hi everybody,
Hope you can help me with this.

One of my websites is currently unreachable due to a theme related fatal error.
I received an automated email from WordPress saying that the problem is related to the “Themify Ultra” theme.
Here’s the error message:

Cannot redeclare themify_theme_menu_nav() (previously declared in /home/customer/www/dentistemolinari.ch/public_html/wp-content/themes/themify-ultra/themify/themify-template-tags.php:1913)

I also received a link to safely access the control panel, but sadly it worked only once. Now, when I click on the link I get a “Recovery Mode not initialized” message.

What should I do?

Thanks!

Paco

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