not able to figure out below message in IDOC generation

Hi Folks,

Not able to figure out the below message in outbound idoc generation.

EDI: Syntax error in IDoc (segment cannot be identified)

Message no. E0078

Diagnosis

The segment E1EDK01 does not occur at the current level of the basic type PEXR2002 (extension ).

This error can have several reasons:

• The segment E1EDK01 is assigned to a group whose header segment does not occur.

• The segment E1EDK01 does not exist in the syntax description of the basic type PEXR2002 (extension ).

• The sequence of segments in the group in which the segment appears is incorrect.

Previous errors ('mandatory' segment or group missing) may be due to this error.

Procedure

Please check the IDoc or the syntax description of the basic type PEXR2002 (extension ).

Please help.

Regards

Ravi