How to see fields appended to extract structure?

Dear Collegaues,

I have added the field PMATN to 2LIS_13_VDITM. In RSA6 I can not see the field among the datasource field, but it is under .Append inside the extract structure. How can I make it a field of the datasource, so it becomes visble in BW after replication?

Hope you can help, will sign points!

Silje