Why does the amount from Form 8959 not appear on Line 62 of Form 1040, added to the amount from Form 8960? Only the amount from Form 8960 is listed and its box checked.

This turned out to be a misunderstanding on our part.   The amount shown on Form 8959 was not what we owed, to be transferred to Line 62 of Form 1040, but what we overpaid, which was accounted for on a subsequent line on Form 1040.  Sorry for the mixup.