Error message

• User warning: The following module is missing from the file system: variable_advanced. For information about how to fix this, see the documentation page. in _drupal_trigger_error_with_delayed_logging() (line 1143 of /var/www/vhosts/web_prod/web_prod/wwwroot/includes/bootstrap.inc).
• Notice: Undefined index: show_remaining_days in date_field_formatter_view() (line 210 of /var/www/vhosts/web_prod/web_prod/wwwroot/sites/all/modules/date/date.field.inc).