Unable to add Apple Store Gift Card to Apple ID balance

I appreciate the response, but I mentioned in the original post that I have the "Silver Card," which should be for "Apple Store." Which means I had already seen the link you posted to identify the card.

I'm not asking which card I have, but rather how to use it outside of the Wallet. The situation is that I traded in a device. Got the gift card. Added it to Wallet and now I would like to use it.

Per the link you posted:

"""

1. Make sure that your card is not an Apple Store Gift Card. Apple Store Gift Cards are gray, white, silver, or gold. You can’t redeem Apple Store Gift Cards in the App Store or iTunes Store. Find out what to do if you have an Apple Store Gift Card or don't know what type of gift card you have.
2. Try entering your redemption code manually. When you redeem an App Store & iTunes Gift Card or redeem an Apple Gift Card, tap or click "You can also enter your code manually." Make sure that you enter the redemption code that begins with "X", not a different number on the card.

"""

1. It *is* an Apple Store Gift Card, which I've already identified. It says: "You can’t redeem Apple Store Gift Cards in the App Store or iTunes Store." Which I am not. I am trying to redeem it in the "Apple Store." Not the Itunes Store. Not the App Store.
2. "Try entering your redemption code manually. " I tried, but says the code is not valid.

Again, the question is: "How do I use an *Apple Store Gift Card* that is currently in my iPhone's Wallet (associated with the correct Apple ID) in the *Apple Store* when purchasing with the same Apple ID?