Airtime Rewards are a hoax

The airtime rewards are a hoax. This is the second time I have received an airtime rewards and cannot redeem it. For the first voucher, I was advised the voucher was already used. For the second voucher, the website requests me to "Please select a reward of your choice"; however nothing further is displayed.

Reaching out to Astron support via the email address is pointless as they do not respond