Affirm Payments Failing

Hi

We get the following error back in order failed message for Affirm payment checkouts:

“Error processing payment. Reason: The payment method type “affirm” is invalid. Please ensure the provided type is activated in your dashboard (https://dashboard.stripe.com/account/payments/settings) and your account is enabled for any preview features that you are trying to use. Order status changed from Pending payment to Failed.”

I logged in and could not see a mention of Affirm on the linked stripe page. From my reading I thought Affirm was available for US customers. We are a UK business but serving US customers on our site. Stripe support were useless and basically didnt even answer my question so thought id ask here as you guys seems so knowledgeable! Are we doing something wrong setup wise or is Affirm not a good choice for us? Thanks for any advice