This is the topic that generates the most "Cypress cannot do this" conversations in real companies, and most of them are half right. Here is the full picture.
Why it is hard. Your app is at app.company.com. Sign-in redirects the browser to login.okta.com. That is a different origin, and Cypress's test code is page code bound by the browser's same-origin policy. When the browser leaves your origin, your test cannot reach the page it lands on.
This is the architecture lecture's fact three, arriving in your sprint.