Which Task Sets up the Rule to create User ID

Summary:

Hi,

At my end, if the desired User ID is duplicated to the existing one for example says below, when creating an User ID.

desired id : abc

existing id : abc

The desired id will be switched to the way of attaching 1 at the end of existing id like abc1.

But, I was wondering where or which task this kind of rule has been set up.

Regards,

SungHyun 

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