checkoutUrl redirects to Shopify store front instead of checkout

We have the exact same issue. We’re headless, with Shopify store on custom domain and password protected.

For logged in users we use Multipass and with it the checkout works correctly:

[Redirects]

  1. https://custom-domain/xyz/checkouts/xyz?key=xyz
  2. https://custom-domain/checkouts/co/xyz

However, when we don’t use Multipass, for anonymous shoppers (I disabled custom domain to have less redirects to report below):

[Redirects]

  1. https://shopify-domain/cart/c/xyz
  2. https://shopify-domain/checkouts/cn/xyz
  3. https://shopify-domain/cart
  4. https://shopify-domain/password