php error after installing plugin

Hello,

After installing the plugin: Code snippets I get the following error at the front – and backend side:

Warning: Use of undefined constant STYLESHEETPATH – assumed ‘STYLESHEETPATH’ (this will throw an Error in a future version of PHP) in /home/customer/www/staging12.avonic.com/public_html/wp-includes/template.php on line 703

Warning: Use of undefined constant TEMPLATEPATH – assumed ‘TEMPLATEPATH’ (this will throw an Error in a future version of PHP) in /home/customer/www/staging12.avonic.com/public_html/wp-includes/template.php on line 706

Fatal error: Uncaught Error: Call to a member function get_page_permastruct() on null in /home/customer/www/staging12.avonic.com/public_html/wp-includes/link-template.php:430 Stack trace: #0 /home/customer/www/staging12.avonic.com/public_html/wp-includes/link-template.php(392): _get_page_link(Object(WP_Post), false, false) #1 /home/customer/www/staging12.avonic.com/public_html/wp-includes/link-template.php(197): get_page_link(Object(WP_Post), false, false) #2 /home/customer/www/staging12.avonic.com/public_html/wp-content/plugins/woocommerce-wholesale-lead-capture/woocommerce-wholesale-lead-capture.functions.php(159): get_permalink(Object(WP_Post)) #3 /home/customer/www/staging12.avonic.com/public_html/wp-content/plugins/woocommerce-wholesale-lead-capture/includes/class-wwlc-scripts.php(286): wwlc_get_url_of_page_option(‘wwlc_general_re…’) #4 /home/customer/www/staging12.avonic.com/public_html/wp-includes/class-wp-hook.php(303): WWLC_Scripts->wwlc_load_front_end_styles_and_scripts(”) #5 /home/customer/www/staging12.avon in /home/customer/www/staging12.avonic.com/public_html/wp-includes/link-template.php on line 430

WP version: 5.8
PHP 7.4.25

Any idea what goes wrong?
Thanks!