The request body must include at least one of accountId or accountAlias. Additionally, you can optionally provide settings for displaying various sections in the Customer Portal.
Settings tied to displaying the Plan Overview section in the Customer Portal. The planOverviewSettings object allows you to show or hide the entire section for a specific account by passing the planOverviewSettings.showSection property.
Upon a successful request, you will receive a response containing a sessionUrl which is the URL to which the user should be redirected to access the Customer Portal.