It may just be because the Jan payouts haven’t been finalized and sent out yet… so it doesn’t know what your “Undistributed payout” actually is. They’ll probably be sent in the next couple days… so I’d check again then.
Payout is happening in the first two weeks of every month, when it’s finished, the satellites will send a receipt to each node, then the payout information will be updated with actual numbers. Before that there is only estimation.