Multiple currencies conversion with DAX

Hello everyone, 

I have tried the below measure to convert source currencies to multiple reporting currencies : 

However this doesn't work, they say : The column MonthID was not found in the input table. 

Here is my model :

I have the column MonthID both in Calendar and Sell Out table with Many-to-Many relationship. 

I manage to solved it with another table containing unique values in the MonthID column and changing the relationship from One-To-Many, however I still need to keep the days in my Calendar table to use time intelligence then. 

Any solution ? 

Thank you very much in advance !!

Pauline