field value and option doesn’t display in invoice

hello sir, i have created an extra field for my products using “Extra Product Options Builder for WooCommerce” by “rednao” and that extra name field displays on checkout, cart, order detail page, etc but it doesn’t show in the invoice.
i tried but couldn’t display the name field of my extra product option in the invoice. can you please help with a piece of code or some way i can display it in my invoice too.
Thanks.

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