Hi, when I use a link to login to my store such as store.myshopify.com/admin it takes me to the admin login and I can login. When using the same credentials on a link such as store.myshopify.com/admin/checkouts.json it asks for the same thing. When I attempt to login it doesn't let me, despite it being the same. When I try to access the link after logging in on /admin then I can view it perfectly fine. I know this because when I test it in private browsing it gives me the error until I login to the admin on that session.
This is the popup - I have tried API key / API secret key for the store as well as the admin's email + pass but it doesn't seem to work. Any help is greatly appreciated, kind regards and thanks, Sam