ErrorCode=-79728 Unknown object type

which situation will generate this error message ?

please help , thanks!

-79728 Unknown object type.

If this object type is a null opaque type, the type is unknown and
cannot be processed. If this object type is a complex type, the data
in the collection or array is of an unknown type and cannot be mapped
to an Informix type. If this object type is a row, one of the elements
in the row cannot be mapped to an Informix type.

Verify the customized type mapping or data type of the object.