Carts deleted after putting in items via API call?

[xlg]

I am facing an issue regarding cart filling via the API. I am including and showing several items from my prestashop on an external website and people should be able to pick things on the external website and then get redirected to the prestashop with a cart already created for them.

I am using the POST

{{webservice_url}}/api/carts&output_format=JSON

endpoint to create a cart and everything is working fine, i get the ID in the response and i can also see in the backoffice that the cart has been created. 

 

in the next step i want to PUT items in the cart using the

{{webservice_url}}/api/carts/<cartID>&output_format=JSON

endpoint and i get an success response and when i open query the carts with the ID i can also see that the items have been added to the cart but when i go to my prestashop backoffice and go to the carts tab the cart is gone? i can only access it by querying the url with the right id. On the page there is also a "Share this cart" URL with which i could use to create my callback to the prestashop but its not working i just get redirected to the landing page with no cart. Its also not cache related since i also tried in an incognito browser. 

Is this wanted behavior or might this be a bug?