EDIT: I did not scroll all the way down. The promo code input field is at the very bottom of the billing page. So disregard this post of mine please. To confirm, I got the $50 credit successfully.

The bit.ly link resolves to this

https://www.digitalocean.com/?refcode=4d7fb2079a96

There is no way to apply a discount code while creating a new account. Looks like you need to open a support ticket to apply discount codes ?

https://www.digitalocean.com/community/questions/any-active-...