Creating package error help

We have a time when we keep getting this error Silanis.ESL.SDK.EslException: Could not create a new package. Exception: Unexpected character encountered while parsing value: . Path '', line 0, position 0. ---> Newtonsoft.Json.JsonReaderException: Unexpected character encountered while parsing value: . Path '', line 0, position 0. at Newtonsoft.Json.JsonTextReader.ParseValue() at Newtonsoft.Json.JsonTextReader.ReadInternal() at Newtonsoft.Json.JsonTextReader.Read() at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.ReadForType(JsonReader reader, JsonContract contract, Boolean hasConverter) at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent) at Newtonsoft.Json.JsonSerializer.DeserializeInternal(JsonReader reader, Type objectType) at Newtonsoft.Json.JsonConvert.DeserializeObject(String value, Type type, JsonSerializerSettings settings) at Newtonsoft.Json.JsonConvert.DeserializeObject[T](String value, JsonSerializerSettings settings) at Silanis.ESL.SDK.EslServerException..ctor(String message, String errorDetails, WebException cause) at Silanis.ESL.SDK.Internal.HttpMethods.PostHttp(String apiToken, String path, Byte[] content) at Silanis.ESL.SDK.RestClient.Post(String path, String jsonPayload) at Silanis.ESL.SDK.Services.PackageService.CreatePackage(Package package) --- End of inner exception stack trace --- at Silanis.ESL.SDK.Services.PackageService.CreatePackage(Package package) at Silanis.ESL.SDK.EslClient.CreatePackage(DocumentPackage package) This is how we are making the package: Dim NewPackage As DocumentPackage NewPackage = PackageBuilder.NewPackageNamed("Test") _ .ExpiresOn() _ .WithEmailMessage("Test") _ .DescribedAs("Test") _ .Build() Dim PackageId As PackageId = Client.CreatePackage(NewPackage)