Thank you for informing us about this.
Could you tell us the name of the board, please? Would it be possible to send us screenshot both from your PC and the iPhone app where it is shown that in the first case the board is shown and in the second case - not?
Hi there, John,
As we checked this board belongs to your partner's Premium account and not your My team working space (which is shown as chosen on your iPhone screenshot). Every account has its own working space, so to be able to see this board click on the My Team words in your app and choose your collaborator's working space.
More about spaces can be found here.
Hope that solves the issue! Please let me know if everything's okay on your end.
Thanks for letting me know everything's okay now! =)