Recipient not getting the email

Hello, thanks for the plugin, I was testing it and found recipient is not getting the email with the gift card. https://prnt.sc/si6EhNDf1Uh2 I’ve tried to purchase a gift card, I got email from my customer account that the order has been completed but didn’t get any email from the recipient’s end. I’ve checked the spam box too.

Btw, I used COD as payment method and completed the order from the woocommerce>order panel. Is it required to use card or other payment method? or this is something else? Please assist. I think our mail delivery is working for all the notificaitons instead of this email only.

Thank you.