We have a Canvas instance using SAML login from an external site. The external site has details for user accounts on it that need to be copied to the Canvas site on login, and we settled on a solution of directing unknown users to a URL where we run some custom code to create their account via the Canvas API.
This works fine, except that the first time the user visits Canvas after their account has been created, they receive a message to say an account for them doesn't exist. This error appears no matter how long the user is delayed before visiting the site, and an API callback confirms that their account does exist and has been created. If the user refreshes the page, they are logged in as expected.
Does anyone have any ideas what might be triggering this error?