Excel summarizes data according to conditions, which helps to see what is wrong.

1.MONTH is a function to extract the month in the date. I don't know why you use it here. Column E is not a date, and M2 is not a date, so it is inevitable that the formula is wrong.

Second, I can't modify the formula for you without knowing the summation conditions. Multi-conditional summation should make the summation conditions clear, so it is better to find a riddler who tells fortune.