Hi Mario,
Welcome to the support forums! I’m happy to help get things sorted out with your list view. Can you recall how the customizations were applied originally? If the plugin was edited directly, then any changes made to the files would have been overwritten when the plugin was updated. That’s why it’s important to add custom templates separately.
The list view single event content template is located at:
/wp-content/plugins/the-events-calendar/views/list/single-event.php
You can customize that template by adding it to your theme like this:
/wp-content/themes/your-theme/tribe-events/views/list/single-event.php
Let me know if you can recall how the template was originally customized or if you need some more guidance on how to apply those customizations to your theme so that they don’t get lost in future updates.
Kind Regards,
Jami