Unable to redeem free beats

Hi,

I recently purchased an Apple Music subscription as a student. I got the email saying that I was eligible for a free Beats Flex. However, when I clicked on the link on the email to redeem it, it said that I can only purchase 1 Beats Flex and to reduce the amount I am adding to the cart. However, I only tried to add one to the cart. So for now, I am unable to redeem the beats. Please help.