Hi,
In SE19 provide the Basic Type(Ex: ORDERS05) and execute, we can get the complete list of sub-segments .
1. check if E1EDP03 is in list, if your using a custom one.
2. Inserting the segements in that sequence is very important.
3. If its processing few IDOCs successfully then please check where and how this segment is populated. It could be possible that based on some condition a segment is populated or sometimes not.
Regards,
Akhila Bidare