I cannot seem to accept an invitation to VPP on an iPad. I've tried with both the prompt and via email. The first time I signed into the App Store at the prompt, I agreed to terms and conditions for organization and I got the confirmation that "This organization can now assign apps and books to you." However, even after a day, my invitation remains unaccepted in the JSS.
If I try to resend or click a link in the email again, I can sign in but I keep getting the message "Unable to Allow Assignment of Content. Check that your AppleID and password are correct and try again."
To be sure that I was typing my password in correctly, I signed out of the App Store and clicked the invitation link again. I had to enter both my AppleID and password, and when I submitted I saw my AppleID appear in the bottom left of the App Store in the background, so I know I was signed in correctly, but I still got the error and my invitation shows as unaccepted in JSS.
This happens with at least 2 AppleIDs, and I've tried creating a few different invitations but they still don't show up as accepted in JSS. Am I missing a step along the way somehow?