COBCH1568 VALUETYPE instance field cannot have circular reference

A field in a valuetype cannot specify a circular reference.

The following example contains a circular reference, which causes the error. Change the specified field type.

valuetype-id myValuetype.
  01 field-1 type myValuetype  *> the field cannot be of type myValuetype
  method-id myMethod-1.
  ...
  end method.
end valuetype.