If you have messaged the seller with the code,then that is all you can do as the buyer.
If the seller doesn't manually enter the code there end,the seller would also be able to mark the item as paid and despatched/collected there end as an option to,so no need to worry.
The code is designed for app users to be fair and not all sellers/buyers have the option of using mobiles and apps
Plus they can always reach out for help on this board 😉
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