Free yard sign - out of stock?

Just signed up for Ring Protect monitoring and got the e-mail with a coupon code for a free yard sign. Clicked on the "redeem" link and the page it took me to showed the sign is "out of stock." I know the offer said "while supplies last" but as a new customer if the free signs are already gone, maybe they shouldn't send out a code? Or is this a temporary stock issue and I'll be able to order a sign eventually?