Pluginextend Problem

I received this error message the other day. This happened at the checkout.

{
    "class": "Error",
    "message": "Cannot access private const WC_Plugin_Updates::VERSION_TESTED_HEADER",
    "code": 0,
    "file": "/www/xxx/public/wp-content/plugins/woocommerce/includes/wc-core-functions.php:2031",
    "trace": [
        "/www/xxx/public/wp-includes/class-wp-hook.php:286",
        "/www/xxx/public/wp-includes/plugin.php:208",
        "/www/xxx/public/wp-includes/functions.php:5589",
        "/www/xxx/public/wp-admin/includes/plugin.php:84",
        "/www/xxx/public/wp-content/plugins/ti-woocommerce-wishlist-premium/includes/pluginextend.helper.php:588",
        "/www/xxx/public/wp-content/plugins/ti-woocommerce-wishlist-premium/includes/pluginextend.helper.php:380",
        "/www/xxx/public/wp-content/plugins/ti-woocommerce-wishlist-premium/includes/pluginextend.helper.php:330",
        "/www/xxx/public/wp-content/plugins/ti-woocommerce-wishlist-premium/includes/pluginextend.helper.php:286",
        "/www/xxx/public/wp-content/plugins/ti-woocommerce-wishlist-premium/ti-woocommerce-wishlist-premium.php:277",
        "/www/xxx/public/wp-content/plugins/ti-woocommerce-wishlist-premium/ti-woocommerce-wishlist-premium.php:302",
        "/www/xxx/public/wp-includes/class-wp-hook.php:286",
        "/www/xxx/public/wp-includes/class-wp-hook.php:310",
        "/www/xxx/public/wp-includes/plugin.php:465",
        "/www/xxx/public/wp-settings.php:394",
        "/www/xxx/public/wp-config.php:51",
        "/www/xxx/public/wp-load.php:37",
        "/www/xxx/public/wp-blog-header.php:13",
        "/www/xxx/public/index.php:17"
    ]
}