SegmentGroup Deserialization

[tomtom4848]

Hi,
I have a little bit trouble with the deserialization of a SegmentGroup...

My Model looks like this (only the relevant parts):

 public class Edifact_IC
{
    public UNB_Segment UNB { get; set; }
    public IC_Message Message { get; set; }
    public UNZ_Segment UNZ { get; set; }
}

[EdiMessage]
public class IC_Message
{
    ......
    public List <SG1_Ref> Ref { get; set; }
    .....
}


//------SegmentGroups-----
[EdiSegmentGroup("RFF", "DTM"),EdiCondition("...", "...", Path = "RFF/0/0")]
public class SG1_Reference 
{
    public RFF_Segment Ref { get; set; }
    public List <DTM_Segment> Date { get; set; }
}


//------Segments-----
......
[EdiSegment, EdiPath("RFF")]
public class RFF_Segment
{
    [EdiValue("X(3)", Mandatory = true, Path = "RFF/0/0")]
    public string Qualifier { get; set; }

    [EdiValue("X(70)", Mandatory = false, Path = "RFF/0/1")]
    public string Reference { get; set; }
.....
}

If I try to deserialize following (only EDIFACT Snipped for testing):
UNA:+.? ' UNB+UNOC:3+XXXXXXXXXX:500+XXXXXXXXX:500+XXXXXX:0610+XXXXXXXXX++VL' UNH+XXXXXXX+XXXXX:X:XXX:XX:2.3c' RFF+AGI:XXXXX' DTM+293:20181001060000:204' UNZ+1+XXXXXXXXXXXX'

the "RFF-Segment" property (Ref) in "SG1_Reference" is always Null. The DTM-Segment in the same SegmentGroup is correct...

If I change the SegmentGroup Class to:

//------SegmentGroups-----
[EdiSegmentGroup("RFF", "DTM"),EdiCondition("...", "...", Path = "RFF/0/0")]
public class SG1_Reference : RFF_Segment
{
    //public RFF_Segment Ref { get; set; }
    public List <DTM_Segment> Date { get; set; }
}

the deserialization works good, but I have now (obviously) not a RFF_Segment property but the "Qualifier" and "Reference" properties.

How do I change the SG1_Reference class that I have a RFF_Segment and a DTM_Segment property?