DATEDIFF Measure not working properli

[GroboBI]

Hi! I'm trying to create a measure that calculates the difference between my beggining date and my end date: 

(Sorry it's in spanish)

The third column is the one im workin on, it's supposed to calculate the datediff between start date and end date, wich it does, but in the "Total" you can see value "335" wich is the total difference between the 2 dates that are in that herarchy.

Instead of 335 it should say 0 , wich is the total sum of the 3 rows.

I will thank any help provided! You can ask me if i didn't explained myself properly.

This is the DAX im using: 

TiempoProceso = CALCULATE(DATEDIFF( MIN( 'log dw_proceso'[Fecha Inicio] ); MAX( 'log dw_proceso'[Fecha Fin]); MINUTE ) ; FILTER('log dw_lote';'log dw_lote'[lote_key]))