Check 1040 line 38 and see if there is a penalty listed. That would have reduced your refund. Where do you see a tax due? Could it be for state? And I wouldn’t apply 100% of a refund to next year. I would want to get some deposited now so I know they got my return and processed it right. If you apply it all to next year you might not know something went wrong until you file 2025.