Beforehand please check my [sample sheet][1].

I'm trying to use `SUMIF` or any specific formula that shows the total amount of income of each month over on the side (March, April, May...)

As noticed the date (month) is not always the same on each column (Date 1, Date 2, Date 3...), it may vary.

I've tried `SUMIF`, `FILTER`, `ARRAYFORMULA`, but haven't had any luck.

Is there any way to do this or do I have to change the whole structure?


  [1]: https://docs.google.com/spreadsheets/d/1gIN3Xvg59B8awxjhjjH6GxMMCY_wrvh8v6uQMVlzj68/edit?usp=sharing