Hi Brandan,
The reason your tax return was less than you expected is, because when you signed up for healthcare.gov you opted to take the maximum tax credit. That means that you were paying less on your premiums than you actually qualified for. So when you did your taxes without reporting on your 1095-a (with form 8962) it told you that your refund was going to be higher. When you submitted form 8962, it told IRS exactly how much you underpaid on your healthcare premiums every month and that amount came out of the rest of your refund.
They did take a long time to send the refund, but that was because of COVID. They did pay interest on the refund they owed you so you got a little extra money for that. They will be send you a letter that explains exactly why you got what you got.
Hope that helps.
