Deserialization List <T>

I mean this error when deserializing:

Invalid wiring type; this usually means that you have overwritten the file without truncating or setting the length; see Using Protobuf-net I unexpectedly got an Unknown Wire Type Exception

This is only a mention of truncating the file, but I am creating a new file

 Stopwatch sw = new Stopwatch();
            List<SomeClass> items = CreateSomeClass();
            sw.Start();
            using (var file = File.Create(fileName))
            {
                var model = CreateModel();
                model.Serialize(file, items);
                file.SetLength(file.Position);
            }
            sw.Stop();
            logger.Debug("Saving/serialization to {0} took {1} m/s", fileName, sw.ElapsedMilliseconds);
            sw.Reset();
            logger.Debug("Starting deserialzation...");
            sw.Start();
            using (var returnStream = new FileStream(fileName, FileMode.Open))
            {
                var model = CreateModel();
                var deserialized = model.Deserialize(returnStream, null, typeof(SomeClass));
            }
            logger.Debug("Retrieving/deserialization of {0} took {1} m/s", fileName, sw.ElapsedMilliseconds);

 public static TypeModel CreateModel()
    {
        RuntimeTypeModel model = TypeModel.Create();

        model.Add(typeof(SomeClass), false)
            .Add(1, "SomeClassId")
            .Add(2, "FEnum")
            .Add(3, "AEnum")
            .Add(4, "Thing")
            .Add(5, "FirstAmount")
            .Add(6, "SecondAmount")
            .Add(7, "SomeDate");
        TypeModel compiled = model.Compile();

        return compiled;
    }

 public enum FirstEnum
{ 
    First = 0,
    Second,
    Third
}
public enum AnotherEnum
{ 
    AE1 = 0,
    AE2,
    AE3
}
[Serializable()]
public class SomeClass
{
    public int SomeClassId { get; set; }
    public FirstEnum FEnum { get; set; }
    public AnotherEnum AEnum { get; set; }
    string thing;
    public string Thing
    {
        get{return thing;}
        set
        {
            if (string.IsNullOrEmpty(value))
                throw new ArgumentNullException("Thing");

            thing = value;
        }
    }
    public decimal FirstAmount { get; set; }
    public decimal SecondAmount { get; set; }
    public decimal ThirdAmount { get { return FirstAmount - SecondAmount; } }
    public DateTime? SomeDate { get; set; }
}

      

        
        
        
      

    

I am new to Protobuf-net, is there something obvious that I am doing wrong / missing?