Can you ask them to take image of the checkout page? Maybe there is not carrier delivery to their address (and they do not give attention to it also i noticed that your checkout is just one step), and without carrier selection, PS does not let them pass payment side.
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Can you ask them to take image of the checkout page? Maybe there is not carrier delivery to their address (and i noticed that your checkout is just one step), and without carrierr selection, PS does not let them pass payment side.