In this case the tag can no longer be used and it must be refunded or exchanged.
In order to return the remaining balance to the user just apply the same policy as for a stolen or lost Cashless tag.
If the Cashless tag was used before being unreadable, it means that the NFC antenna has been damaged during its use. Do not drill or bend a cashless tag as this may break the antenna.
If the tag is unreadable from the beginning please send us the information with the short ID Cashless tag. With a view to continuous improvement, we will go up the manufacturing chain to identify the potential source of error.