We have created a sharepoint site in order to share files with board members (who are external). In order to give them access, we have created Guest User accounts for them via Azure AD. I would like to use the Approval flow to get their approval on documents. However, they receive an that says, "Your organization does doesn't allow access to Microsoft Flow via your work or school email," when they try selecting Approve or Reject in the email.
I am not able to use the "Send Email with Options" flow because I need to be able to track who approves/rejects the docuement and the date that they do so.
If the users are added as guest users to our tenant and they are authenticated, why can't they respond to the Approval Flow?