How to fix `array literal error' when merging formulas?

I made a Google sheet with a pivot formula. To replace the empty cells with zeros, I have written formula. The formula is merged from 3 individual formulas. The formulas work individually, but after merging I get an Array Literal error. What am I missing?

link to the Google Sheet https://docs.google.com/spreadsheets/d/17De4sUlkBmDKoFw4DR9serilGFcKQCur2PlvQ6RaMKk/edit?usp=sharing

Merging the formulas gives an array literal error message, where I expect a working outcome

I hope someone can help me.