Error creating PWO - [2133232] Processing requires authentication via employee.

When I try to create PWO from process calling script 

Dim dbPWO = Session.Source.CreateNew("PersonWantsOrg")
Dim Bag As New PropertyBag()
Bag.PutValue("ObjectKeyOrdered","<Key><T>QERReuseUS</T><P>xxx</P></Key>")
Bag.PutValue("UID_PersonOrdered", "xxx")
Bag.PutValue("OrderState", "Assigned")

dbPWO.CallMethod("FillOrder", Bag)
dbPWO.Save(Session)

i'm getting an error

[810306] Error running 'OnSaving' in logic module 'QER.Customizer.PersonWantsOrg'.
[2133232] Processing requires authentication via employee.

How to run a script as an employee?