Many do-shortcode.php errors

After upgrading to Kadence Theme, getting suddenly many lines like below in error_log:

[08-Dec-2021 07:17:31 UTC] PHP Warning: Use of undefined constant grey1 – assumed ‘grey1’ (this will throw an Error in a future version of PHP) in /home/tray3/public_html/wp-content/plugins/shortcodes-ultimate-maker/includes/do-shortcode.php(122) : eval()’d code on line 25

Solution?