ERROR NullPointerException in tMap

[EvoticTalend]

I have a flow with 2 tMaps doing the SAME THING minus the joins (sending columns from a csv file to an output to send again to a DDBB), but there is an error NULLPOINTEREXCEPTION in the second tMap.

 

As I said, the tMaps are doing the same (only the joins are different but I have the same joins in other flows and there is no error)

THIS IS THE TMAP NUMBER 1

 

THIS IS THE TMAP NUMBER 2

 

THIS IS THE ERROR

 

WHY IN THE SECOND TMAP I HAVE AN ERROR AND NOT IN THE FIRST?

Thank you very much.

[XJ_1630]

my wild guess: the datasets in tMap2 contains null values

[EvoticTalend]

The files are the same in the first tmap and second... in the frist tmap the flow is correctly executed but in the second there is an error even in the first row. So strange.