I dont understand 2020 Massachusetts tax return

No one else can see your screen or your tax return.   Could you ask some specific questions?

We do not know what might have changed with your income or tax withholdings for the state, or if there is some form that is not yet ready for your state which is affecting your state tax return results at this time.  There are many state forms that are not yet ready.  Click Review to see if there is a form that is still affecting the calculations on your state return.   Or get out a copy of your 2019 W-2 and compare it to your 2020 W-2 and see what is different in box 17.  Or.....print copies of both years state returns and compare them line by line to see what is different.