If you are redeeming a gift card and you get a message that your gift card is not working, don't panic, here are some tips on what you can do if your gift card is not working.
First of all, all gift cards have one thing in common, not all gift cards are available worldwide, most gift cards can only be used in the country where you purchased the gift card. So you need to first confirm which country you are purchasing the gift card for, and if a prompt comes up saying that the country region is wrong, don't worry, your card is not invalid. For example, if you have a US Amazon gift card, but you use your German Amazon account to recharge it, you may not be able to redeem it, it will prompt you that your gift card does not work, in which case you will need to use your US Amazon account to redeem it. In other words, it's best to redeem the gift card in the country where you bought it with your account.
Secondly, some gift cards will show "claim code locked", which means your gift card cannot be reloaded to your account temporarily, you need to ask the official customer service of the gift card to unlock the gift card and then reload it to your account. Some other gift cards will show "The gift card claim code is invalid.", this situation is to suggest that you may have entered the wrong gift card code, please re-confirm the card code and re-enter.
For Steam gift cards, in addition to the three cases mentioned above, it may also appear that the code may not yet have been activated. You need to confirm whether the gift card is activated before topping up your Steam account.
In the case of Google Play gift cards, in addition to the above, you may encounter some other problems, such as "Your code could not be redeemed." or "That code didn't work. Try again. If the code is for a specific app, redeem it in that app." This means there is something wrong with the code and you need to re-enter it or use a specific app to recharge. There is also a case of "We need more info to redeem your gift card.", which means that your gift card cannot be reloaded to your account at the moment and you need to contact Google officials to solve the problem.
Of course, you may encounter various problems during the process of redeeming your gift card. In case you encounter similar problems with your gift card not working, don't worry, visit the official gift card website to check the problem and you will always find a solution.