Undefined error

Hello, I keep getting this error message when I activate the add-on (had to deactivate in debug mode to keep the website live, otherwise it makes it crash):

Uncaught Error: Call to undefined function str_contains() in /homepages/1/d619295783/htdocs/clickandbuilds/BelAirClassique/wp-content/plugins/enhanced-e-commerce-for-woocommerce-store/admin/class-conversios-admin.php:70 Stack trace: #0 /homepages/1/d619295783/htdocs/clickandbuilds/BelAirClassique/wp-includes/class-wp-hook.php(288): Conversios_Admin->dequeue_css('') #1 /homepages/1/d619295783/htdocs/clickandbuilds/BelAirClassique/wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters(NULL, Array) #2 /homepages/1/d619295783/htdocs/clickandbuilds/BelAirClassique/wp-includes/plugin.php(478): WP_Hook->do_action(Array) #3 /homepages/1/d619295783/htdocs/clickandbuilds/BelAirClassique/wp-admin/admin-header.php(118): do_action('admin_print_sty...') #4 /homepages/1/d619295783/htdocs/clickandbuilds/BelAirClassique/wp-admin/edit-form-advanced.php(419): require_once('/homepages/1/d6...') #5 /homepages/1/d619295783/htdocs/clickandbuilds/BelAirClassique/wp-admin/post.php(198): include('/homepages/1/d6...') #6 {main} t

I like this app; would be sad to it go ??

Thanks for your help!

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