EDI: Syntax error in IDoc (too many repetitions of a segment)

What causes this issue?

According to the syntax description of the basic type &v1& (customer
enhancement &v2&), the segment &v3& can be repeated a maximum of &v4&
times. However, this segment occurs more 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&).

Error message extract from SAP system. Copyright SAP SE.