Please make sure that:
You are using an Android device (Phone/tablet) operating in Android version 7.0 and above
The card you are trying to charge supports contactless transactions
Your device (phone/tablet) supports NFC technology and the NFC setting is activated.
Additionally, you can try tapping the card lightly on the back of your device until you hear the characteristic sound indicating that the card details have been successfully read. Each device reads the card at a different point, you can place a small sticker in the right place to locate it more easily next time!