I want to check my apple gift card digit with my serial number

I do not think what you wish to do is possible.

This link will take you to the section of the support article about what to do if your code is unreadable If you can't redeem your Apple Gift Card or App Store & iTunes Gift Card - Apple Support

Please follow the steps in this Apple Support article. 

If you can't redeem your Apple Gift Card or App Store & iTunes Gift Card - Apple Support

If after reviewing the article, and following the directions in the article, you need additional assistance please follow the link below to contact official Apple Support. 

Contact Apple Gift Card Support

Please follow the steps in this Apple Support article. 

If you can't redeem your Apple Gift Card or App Store & iTunes Gift Card - Apple Support

If after reviewing the article, and following the directions in the article, you need additional assistance please follow the link below to contact official Apple Support. 

Contact Apple Gift Card Support

And the same answer works.

Please follow the steps in this Apple Support article. 

If you can't redeem your Apple Gift Card or App Store & iTunes Gift Card - Apple Support

If after reviewing the article, and following the directions in the article, you need additional assistance please follow the link below to contact official Apple Support. 

Contact Apple Gift Card Support

I mistakenly scratched off my apple gift card digit I have my receipt I want to check the code with the serial number

Can I check my card digits with my serial number

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