Problem with Woocommerce Email Customizer

I purchased the WooCommerce Email Customizer plugin, but I can’t activate it. I entered the code I received with the purchase into the “Auto update key” section on the settings page and then clicked the “Save Key” button at the bottom. Unfortunately, I can’t save the templates I’ve already edited. What do I need to do to activate the product and get it working properly?

Thank you very much

Greetings from Switzerland

Patrick

https://leo-elements.ch/wp-admin/edit.php?post_type=viwec_template&page=viwec-auto-update