The first message is pretty self explanatory – the code has exceeded its period of validity and is no longer redeemable . In this case, you can use a different code, or perhaps there’s currently no working codes for your Udemy orders.
Read moreHow can I get free Udemy credits?
The Udemy credits program (“Program”) is offered to anyone with a Udemy account at the sole discretion of Udemy, Inc. Participation in the Program is automatic. You will earn Udemy credits (“Credits”) any time you complete certain activities that are eligible for receiving Credits (each an “Eligible Activity”).
Read more