System.NullReferenceException:“Object reference not set to an instance of an object.”

[AmberHan]

Plist.Deserialize<SomeClass>(plistdata);
class SomeClass
{
[PlistProperty("QueryResponses")] public QueryResponses? QueryResponses { get; set; }
[PlistProperty("Status")] public string? Status { get; set; }
}
System.NullReferenceException:“Object reference not set to an instance of an object.
because the object QueryResponses may or may not have；

[AmberHan]

plistdata don't have QueryResponses: Object reference not set to an instance of an object.
public QueryResponses QueryResponses { get; set; }

plistdata have QueryResponses: Object of type 'PlistAPI.General.Plist' cannot be converted to type System.Nullable1[QueryResponses]'.
public QueryResponses? QueryResponses { get; set; }

[flightlex]

plistdata don't have QueryResponses: Object reference not set to an instance of an object. public QueryResponses QueryResponses { get; set; }

plistdata have QueryResponses: Object of type 'PlistAPI.General.Plist' cannot be converted to type System.Nullable1[QueryResponses]'. public QueryResponses? QueryResponses { get; set; }

I apologize for the late answer. Have you tried PlistConverter attribute?
Its not meant to automatically convert different data types itself. About the exceptions, use PlistSettings with PlistInvalidDataHandlingType.ReturnNull, if the value may be null