ALE IDOC issue where a field in one Z-segment is missing

I am using BD10 for sending one material for one SAP system to other system.

The idoc type is MATMAS05 and there is a extension ZMATMAS05A. The segment type ZE1MARAM_WMS

has two versions, first version has 13 fields and 2nd Versions has 14 fields.

So, when idoc is created in most cases it shows 14 fields and in some cases 13 fields

so, can anyone help me to find why its showing 13 fields.