A Database name was required ( What it means )

[Ehaviv]

Hi

Do someone can explaine this GIGO

Platform : NX MANAGER 8.5

Clone type : Clone operation
Clone action : Retain
Clone Default Naming : UserName

========================= This code ===================
ufs.Clone.Iterate(input_part_name)

Try
ufs.Clone.SetAction(input_part_name, UFClone.Action.Clone, "")
ufs.Clone.setNaming(input_part_name, UFClone.NamingTechnique.UserName, output_part_name)
Catch e As Exception
lw.WriteLine("On Catch - input_part_name = " & input_part_name)
lw.WriteLine("On Catch - output_part_name = " & output_part_name)
lw.WriteLine("The process failed: {0}." & e.ToString())
Exit Sub
End Try

===================== Give this ListingWindow output =================

On Catch - input_part_name = @DB/2000AB12345-0021/-
On Catch - output_part_name = @DB/a1_2000AB12345-0021/-

The process failed: {0}.NXOpen.NXException: A Database name was required and
an O/S file name received
at NXOpen.UF.UFClone.SetNaming(String input_part_name, NamingThechnique naming_thechnique, String output_part_name)
at app path in line 120
=========================================================================

My problem is that @DB/a1_2000AB12345-0021/- is this is not A Database name

So wy I get this error ?

Thanks in advanced