I write some data to an excel file and when I run my code again I want to delete the file and create the file again

Issue is that it says PowerShell is locking the file .

<I get the $email object here, $email>

 $outputFile = "d:testfile.xlsx"
 $excel = New-Object -ComObject Excel.Application
 $workbook = $excel.Workbooks.Add()
 $sheet = $workbook.Worksheets.Item(1)

 $row = 1
 $sheet.Cells.Item($row, 1) = "Subject"
 $sheet.Cells.Item($row, 2) = "Body"
 $row++
 $sheet.Cells.Item($row, 1) = $email.Subject
 $sheet.Cells.Item($row, 2) = ($email.Body.Content[0..1999] -join  '')

and then run the following

 [System.Runtime.Interopservices.Marshal]::ReleaseComObject($workbook)
 [System.Runtime.Interopservices.Marshal]::ReleaseComObject($excel)
 [System.GC]::Collect()
 [System.GC]::WaitForPendingFinalizers()
 Remove-Variable workbook, excel

When I run this code again it says that the file is being used by another process ie PowerShell

How can I delete the file everytime before I start ?

I have tried deleting from the start but it says the file is locked . Its as if PowerShell hasn’t released it