Credits have a validity period of 60 days, so make sure you use them in time! The expiry date is noted in the My Credits section of your account.
NOTE: The expiration date is set for Central European Time (CET), so make sure you redeem your credit(s) at least 1-2 days earlier when you’re in a different time zone so they don't expire before you get to use them. Once credits expire, it is not possible to replace them.
Any further questions? Please contact Customer Support as they're always ready to help!