Store Checkout/Global Checkout Issue

I have created a flow and I have been trying to show it on front end. In this link Override Global Checkout aka Replace Checkout page (cartflows.com) there is a drop down menu. Where I have to select Cartflow Checkout page as below (this image is from the link I shared in this paragraph).

Now below is the screenshot of my settings page where I have setup a flow and want to activate it now in my global settings. This does not have any dropdown.

Now I am unable to change my Global Checkout Page using Cartflow and default WooCommerce one is there.