Search guest’s cart

Hi
My website uses phone numbers as usernames. and I have designed checkout pages and the link I sent to customers is like this. so the product is directly added to the cart :

https://site.com/mycheckoutpage?add-to-cart=000

in the checkout page, user is only required to input his name and his number, and my website automatically creates a user account for that name and phone number after he clicks checkout button and completes the order.

As Its good for the checkout process to be as simple as possible, I don’t force them to login on checkout page.

what I really need, is that guest should be able to add product to his cart

then, the plugin checks from the username after clicking the checkout button (in my case, billing_phone), to see if the user purchased the product before

and if that user_id did purchase, the order should be prevented

else, the checkout would be completed.

is this possible with he pro version of your plugin?