It is normal to loose the user's data in the insert form after a postback has been performed. Edit item values are preserved because they are fetched from the database every time the item gets in Edit mode. But with insert item you could not automatically load the old values. However, you could create a hashtable to store the user input from the insert form, and then you could store this hashtable in the Session object. You could check this
help topic for more information on getting user input in hashtable.
Additonally, you do not need to execute one and the same code in both ItemCreated and ItemDataBound events. You could place your code either in the ItemDataBound event or in the ItemCreated.
Give this suggestion a try and check if it works for you.
All the best,
the Telerik team
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