Fatal error: Uncaught Error: Undefined constant "WC_VERSION" in /var/www/vhosts/laesquina.es/httpdocs/wp-content/plugins/woocommerce-pay-for-payment/inc/class-pay4pay.php:40
Stack trace:
#0 /var/www/vhosts/laesquina.es/httpdocs/wp-content/plugins/woocommerce-pay-for-payment/inc/class-pay4pay.php(16): Pay4Pay->__construct()
#1 /var/www/vhosts/laesquina.es/httpdocs/wp-content/plugins/woocommerce-pay-for-payment/woocommerce-payforpayment.php(32): Pay4Pay::instance()
#2 /var/www/vhosts/laesquina.es/httpdocs/wp-includes/class-wp-hook.php(324): pay4payment_plugin_init()
#3 /var/www/vhosts/laesquina.es/httpdocs/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters()
#4 /var/www/vhosts/laesquina.es/httpdocs/wp-includes/plugin.php(517): WP_Hook->do_action()
#5 /var/www/vhosts/laesquina.es/httpdocs/wp-settings.php(578): do_action()
#6 /var/www/vhosts/laesquina.es/httpdocs/wp-config.php(55): require_once('...')
#7 /var/www/vhosts/laesquina.es/httpdocs/wp-load.php(50): require_once('...')
#8 /var/www/vhosts/laesquina.es/httpdocs/wp-blog-header.php(13): require_once('...')
#9 /var/www/vhosts/laesquina.es/httpdocs/index.php(17): require('...')
#10 {main}
thrown in /var/www/vhosts/laesquina.es/httpdocs/wp-content/plugins/woocommerce-pay-for-payment/inc/class-pay4pay.php on line 40