Error encountered looking up tax amount System.Web.Services.Protocols.SoapException: Server was unable to read request. ---> System.InvalidOperationException: There is an error in XML document (2, 579). ---> System.FormatException: Input string was not in a correct format. at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal) at System.Number.ParseDouble(String value, NumberStyles options, NumberFormatInfo numfmt) at System.Double.Parse(String s, NumberStyles style, NumberFormatInfo info) at System.Xml.XmlConvert.ToDouble(String s) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReader1.Read4_Cart Item(Boolean isNullable, Boolean checkType) at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReader1.Read32_Loo kup() at Microsoft.Xml.Serialization.GeneratedAssembly.ArrayOfObjectSerializer8.Deseriali ze(XmlSerializationReader reader) at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events) --- End of inner exception stack trace --- at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events) at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle) at System.Web.Services.Protocols.SoapServerProtocol.ReadParameters() --- End of inner exception stack trace --- at System.Web.Services.Protocols.SoapServerProtocol.ReadParameters() at System.Web.Services.Protocols.WebServiceHandler.CoreProcessRequest()