Sharing violation on path in c# (for xamarin.ios)

I am developing xamarin.ios application and it worked well before two three months without any problem. But right now I am getting the below error occasionally.

“ Sharing violation on path /Users/vofox3/Library/Developer/CoreSimulator/Devices/A357B468-BDBA-4397-B2D7-40A6333E93CD/data/Containers/Data/Application/5D715BAA-DD43-404D-8D94-0E11224745E8/Documents/WBidMax/User.xml”.

I am using below code to read the User.XML file.

/// <summary>
      /// Load configuration details from XML
      /// </summary>
      /// <typeparam name="T"></typeparam>
      /// <param name="filePath"></param>
      /// <returns></returns>
      public static T DeserializeFromXml<T>(string filePath)
      {
          try
          {

              T wBidConfiguration;
              using (TextReader configurationFileStream = new StreamReader(filePath))
              {
                  XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));
                  wBidConfiguration = (T)xmlSerializer.Deserialize(configurationFileStream);
                  return wBidConfiguration;
              }


          }
          catch (Exception ex)
          {
              throw;
          }
      }

The below code I am using to write the XML file.

public static bool SerializeToXml<T>(T configType, string filePath)
       {
           bool status = false;
           try
           {
               XmlWriterSettings xmlWriterSettings;
               XmlSerializerNamespaces xmlSerializerNamespaces;

               xmlWriterSettings = new XmlWriterSettings
               {
                   Indent = true,
                   OmitXmlDeclaration = false,
                   NamespaceHandling = NamespaceHandling.OmitDuplicates,
                   Encoding = Encoding.UTF8
                   CloseOutput = true


               };
               xmlSerializerNamespaces = new XmlSerializerNamespaces();
               xmlSerializerNamespaces.Add("", "");

               if (!Directory.Exists(Path.GetDirectoryName(filePath)))
                   Directory.CreateDirectory(Path.GetDirectoryName(filePath));

               using (FileStream configurationFileStream = new FileStream(filePath, FileMode.Create))
               {

                   using (XmlWriter xmlWriter = XmlWriter.Create(configurationFileStream, xmlWriterSettings))
                   {
                       XmlSerializer serializer = new XmlSerializer(typeof(T));
                       serializer.Serialize(xmlWriter, configType, xmlSerializerNamespaces);
                   }
               }

               status = true;
           }
           catch (Exception ex)
           {
               status = false;
           }

           return status;
       }

Could you please tell me the reason for this Error?