SaveFileBytesToUserTempFolder returning an error message

We're getting a similar error:

Here's the section of the code that gets the CSV string that is converted to Byte:

                Dim ds As New DataSet
				Dim csvContent As New Text.StringBuilder
				Dim qualifier As String = StageConstants.ParserDefaults.DefaultQuoteCharacter
				Dim delimiter As String = StageConstants.ParserDefaults.DefaultDelimiter
				
				csvContent.AppendLine("Intercompany Detail")
				csvContent.AppendLine("Workflow Profile: " & WFProfile)
				csvContent.AppendLine("Workflow Scenario: " & WFScenario)
				csvContent.AppendLine("Workflow Time: " & WFTime)			

                Dim methodQuery As String = "{" & WFProfile & "}{" & WFScenario & "}{" & WFTime & "}{}{}{V#[YTD]}{True}{}{}{}{}{}" 

                If Not String.IsNullOrEmpty(WFTime) Then
                    Using dbConnApp As DbConnInfo = BRApi.Database.CreateApplicationDbConnInfo(si)					
                        ds = BRApi.Database.ExecuteMethodCommand(dbConnApp, XFCommandMethodTypeId.ICMatchingForWorkflowUnitMultiPlug, methodQuery, "PlugAccounts", Nothing)
"Get the IC Detail"
						'Export the data
						Dim fileName As String = "IC_Detail.csv"

						'********* debug info *********	
						brapi.ErrorLog.LogMessage(si, "ADU_SoluitonHelper.Extract_WFU_IC_Matching_Plug_Accounts" & vbCrLf & 
														"csvContent: " & csvContent.Length)
						'****************************** 					
						'Export csvContent to User Temp Folder
						Dim fileBytes As Byte() = Encoding.UTF8.GetBytes(csvContent.ToString)
	'					Threading.Thread.Sleep(5000) ' 5000 milliseconds = 5 seconds
						BRApi.Utilities.SaveFileBytesToUserTempFolder(si, si.UserName, fileName, fileBytes)
						
					End Using
				End If

The application is on the cloud so we can't use http://localhost:50002/OneStreamApp/SVC/XFFileSystem.svc