Error in WooCommerce Products

If i go to Products > All products i get a critical error:

Foutdetails
===========
Een fout van het type E_ERROR werd veroorzaakt op regelnummer 916 van
het bestand /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-product.php.
Foutmelding: Uncaught TypeError: strtolower(): Argument #1 ($string)
must be of type string, array given in
/www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-product.php:916
Stack trace:
#0 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-product.php(916):
strtolower(Array)
#1 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php(801):
WC_Product->set_tax_status(Array)
#2 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/data-stores/class-wc-product-data-store-cpt.php(373):
WC_Data->set_props(Array)
#3 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/data-stores/class-wc-product-data-store-cpt.php(189):
WC_Product_Data_Store_CPT->read_product_data(Object(WC_Product_Simple))
#4 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/class-wc-data-store.php(159):
WC_Product_Data_Store_CPT->read(Object(WC_Product_Simple))
#5 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-product.php(138):
WC_Data_Store->read(Object(WC_Product_Simple))
#6 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/class-wc-product-simple.php(24):
WC_Product->__construct(13494)
#7 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/class-wc-product-factory.php(46):
WC_Product_Simple->__construct(13494, Array)
#8 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/wc-product-functions.php(73):
WC_Product_Factory->get_product(13494, Array)
#9 /www/kapsalonsubliem_293/public/wp-content/plugins/woocommerce/includes/admin/class-wc-admin-assets.php(357):
wc_get_product(13494)
#10 /www/kapsalonsubliem_293/public/wp-includes/class-wp-hook.php(324):
WC_Admin_Assets->admin_scripts(‘edit.php’)
#11 /www/kapsalonsubliem_293/public/wp-includes/class-wp-hook.php(348):
WP_Hook->apply_filters(NULL, Array)
#12 /www/kapsalonsubliem_293/public/wp-includes/plugin.php(517):
WP_Hook->do_action(Array)
#13 /www/kapsalonsubliem_293/public/wp-admin/admin-header.php(118):
do_action(‘admin_enqueue_s…’, ‘edit.php’)
#14 /www/kapsalonsubliem_293/public/wp-admin/edit.php(411):
require_once(‘/www/kapsalonsu…’)
#15 {main}
? thrown

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