Why isn't my 10% off welcome discount code working for email signups?

I set up a WELCOME 10% OFF discount for customers who have signed up for emails but haven’t made a purchase yet. I used the Automated Shopify Email feature and the emails are going out fine but when you click through to the shop the discount isnt available to use - screen shot below. I don’t understand why its not ‘available’ when the profile of the user is a match and the discount link it literally provided in the email they get?

@KristenOmnia

Welcome to the Shopify community!
Thanks for your good question.
Contact to the Shopify Support team might be they help you.
https://help.shopify.com/en/questions#/contact