When in customizing mode of the website, 404 Not found for checkout page occurs

Store Design
1

Im using Prestige Theme and when customizing it, when I select Checkout page it shows 404 not found, it worked earlier and now I’m stuck, I can’t customize it. Btw if you try accessing the website which is stormbuys.com and try checking out, it works fine, but I can’t customize it at all. I searched all possible info/fix in shopify discussion and in internet, but no luck, can anybody help me please?

I have included the screenshots as well as zip file

2

For everyone out there with trial or basic plan, please clear the cache and cookies for shopify and try accessing Checkout page again in Customize mode

That worked for me.