EDI: Syntax error in IDoc (too few repetitions of a group)

What causes this issue?

According to the syntax description of the basic type &v1& (customer
enhancement &v2&), the segment group &v3& must be repeated at least
&v4& times. However, this segment group occurs less frequently in the
<DS:GLOS.IDoc>IDoc</>.

How to fix this error?

Please check the IDoc or the syntax description of the basic type &v1&
(customer enhancement &v2&).

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