Quantity Conversion Interface: export parameters <> ext. prog. parameters

What causes this issue?

The export parameters structure name specified in Table OIB04 does not
correspond to the actual export parameters expected by the quantity
conversion function routine(s) (for example, the API c-code routines).
Check the entries in Table OIB04. Check the structures in the ABAP
Data Dictionary, and change them to match the expected export parameters
within the called function routines, that is, field type, length, and
the order of sequence.

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