Measure is not displaying sum as aggregation option

Hello.

I added a table with the cost which I want to join with my fact table.

I created an analytic view with both tables and made the join by material, when the cost measure is added to the output in the semantic layer is not treated as a measure but like an attribute or something else because it does not let me choose sum as aggregation at report level.

What am I doing wrong??

At report level, the measure only allows count as aggregation:

Thanks in advance.