"Did your client pay full price"

Here's the kicker:

"only entry is in Monthly advance payment"

What we have here is the need to reconcile what the person paid, what advanced benefit they were given based on their projections to the marketplace, what their actual income is for this tax year, and how that all relates to the computations for whether or not there will be any reimbursement required or whether the person qualifies for more credits or not. It's monthly, because life circumstances can change through the year, of course. It seems this person had advance credits paid on their behalf to their insurance provider to reduce their premium costs. That doesn't by itself define if their premium is affordable or not, or if their resulting income means the advance should not have been provided.