Adding to list in bpel

Question

Im trying to append an element to a list of objects but i'm getting a NullpointerException, can someone help me.

                            <if name="If1">
                                <condition>1 = $addFlightCalled</condition>
                                <assign name="Assign">   <----- THIS IS WHERE I GET A NULLPOINTER
                                    <extensionAssignOperation>
                                        <bpelx:append>
                                            <bpelx:from>$tempFlight</bpelx:from>
                                            <bpelx:to>$Itenerary/flightBookings</bpelx:to>
                                        </bpelx:append>
                                    </extensionAssignOperation>
                                </assign>
                                <else>
                                    <assign name="Assign3">
                                        <copy>
                                            <from variable="tempFlight"/>
                                            <to>$Itenerary/flightBookings/FlightBookings</to>
                                        </copy>
                                    </assign>
                                </else>
                            </if>
...

Can someone help me.

Answer 1

$Itenerary/ns0:Flights/ns0:FlightBookings[$ForEach1Counter]/ns0:bookingNumber $CancelFlightIn.parameters/arg0 $Itenerary/ns0:Flights/ns0:FlightBookings[$ForEach1Counter]/ns0:price $CancelFlightIn.parameters/arg1