Invoice Distribution Account No Longer Defaults Segment Values

Typically, when a user clicks on the AP invoice distribution line to enter the distribution account, three of the nine segments default to all zeroes.  Recently, without anything changing, these values no longer default in.  This is only happening to one user; the zeroes default for all the other users.  Why is only one user affected and what change can I make for the zeroes to default?

Thanks,

Aileen