Auth0 + Okta SWA

I currently use Auth0 for my authentication but one of my customers would like to auto-fill their credentials inside the login page using Okta SWA (https://help.okta.com/en/prod/Content/Topics/Apps/Apps_App_Integration_Wizard_SWA.htm)

However, they say that Okta does not seem to recognize/auto-fill the Auth0 login page. Any idea what could be causing this issue?