Select error: ORA-24334: no descriptor for this position

i have a window that upon open() retrieves data from a sql for a datawindow.
This retrieval returns about 500 records.
I also have a function call in the retrieverow() event which cursors through another table and obtains data to be concatenated based on the ID from the datawindow's resultset.
But i get the following:

Select error: ORA-24334: no descriptor for this position

i think , it might have something to do with the fact that the transaction object sqlca connection is still trying to finish the SQL the datawindow executed, while i'm trying to loops.

i tried creating a new transaction object for the cursor - but that didn't resolve the error message.

the dw is using sqlca and so is the cursor.
how do i create a new transaction object specific to the cursor -so that it won't crash ?

thanks in advance.