Look like your store is still a development store? Were you able to do this earlier?
Hi @Propero , yes I was. My website will be live in 3 hours so I am freaking out! I contacted shopify support, they told me that it is because I had to enable my app "shipping rates by zipcodes" to take the hand on checkout. But my app is enabled for 1 week (see screenshot below), and I was able to do a complete checkout until today.
So I don't know what to do, I am waiting for the app support reply for now.