Exception when Imports one or many catalogs, metadata and dictionaries from an xml source

Hi,

I am using CatalogImportExport class to import catalogs, metadata and dictionaries from an xml source to episerver commerce and sometime it work but sometime it throw an exception like below

Could you please give me a hand

My code

using (var catalogXmlStream = new MemoryStream())
{
catalogXDoc.Save(catalogXmlStream);
// set stream pointer to beginning
catalogXmlStream.Seek(0, SeekOrigin.Begin);

// import back by episerver import export
CatalogImportExport cie = new CatalogImportExport();
cie.Import(catalogXmlStream, true);
}

The job is running. - Starting execution of: Plus.Web.Business.ScheduleTasks.NewScheduledJob.APIServiceENEGScheduledJob
Invalid operation. The connection is closed.
<br>
at System.Data.SqlClient.SqlInternalConnectionTds.ValidateConnectionForExecute(SqlCommand command)
at System.Data.SqlClient.SqlInternalTransaction.Rollback()
at System.Data.SqlClient.SqlTransaction.Rollback()
at Mediachase.Data.Provider.TransactionScope.ThreadStaticTransactionScope.Dispose()
at Mediachase.Data.Provider.TransactionScope.Dispose(Boolean disposing)
at Mediachase.Data.Provider.TransactionScope.Dispose()
at Mediachase.MetaDataPlus.Internal.CatalogMetaObjectRepository.UpdateBatch(IDictionary`2 metaObjectsByLanguage)
at Mediachase.Commerce.Catalog.ImportExport.Import.MetaDataReader.AcceptChanges(Dictionary`2 metaObjects)
at Mediachase.Commerce.Catalog.ImportExport.Import.NodesReader.Read(ImportCatalogNodeCache relationCache)
at Mediachase.Commerce.Catalog.ImportExport.Import.Importer.Import(Stream stream, String sourceDirectory, Boolean overwrite)
at Electrolux.Core.Catalog.Import.EdenImportService.Import(String language, IEdenCatalogConfigs catalogConfigs, IEdenMappingConfigs mappingConfigs, IEdenURLBasePathConfigs urlBasePathConfigs, XmlNode node)
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at Electrolux.Core.Catalog.Import.EdenImportService.Import(String language, IEdenCatalogConfigs catalogConfigs, IEdenMappingConfigs mappingConfigs, IEdenURLBasePathConfigs urlBasePathConfigs, XmlNode node)
at Electrolux.Web.Business.ScheduleTasks.NewScheduledJob.NewEDENAPIServiceScheduledJobBase.Execute()

Thanks

Thao Pham