This section of the Premium Tax Credit (1095-A form) section directs you to add the totals of all 1095-A forms together for lines 33A, 33B, and 33C. However, if you read the instructions for Form 8962, it explicitly says you are NOT supposed to add the amounts together for column B. The column B totals should be the same on all your 1095-A forms, and you should only enter that amount, not add them together.
When filling out my tax return on CreditKarma, my estimated refund jumped from $5000 to $10,000 after filling out the Premium Tax Credit section. I decided something must be wrong so I took the time to redo everything on TurboTax. TurboTax told me that I actually need to repay about $600 of tax credit. I figured out that the issue has something to do with Form 8962, and noticed Line 11 Column B was massively different from last year so I read the instructions. After entering the correct number, CreditKarma and TurboTax gave me similar results.