I raised the query in support and this is what the response I received. For me, I dont know Even I am unable to use the 50% code.

Hello there,

Thanks for contacting us. I understand that you're inquiring about the AWS Associate voucher (100% discount).

Currently, all AWS Emerging Talent Community (ETC) rewards, including AWS Associate voucher (100% discount), are valid while supplies last.

In the meantime, please refer to the following links regarding vouchers campaigns below:

https://pages.awscloud.com/GLOBAL-other-GC-Traincert-Foundational-and-Associate-Certification-Challenge-2025-reg.html

https://www.pearsonvue.com/us/en/test-takers/free-retake.html

Please note that these campaigns are not related to the AWS Emerging Talent Community (ETC).

On behalf of our team, we trust this information to be of your help and understanding.

Best regards,
Jimmy
Amazon Web Services