This feature is only available to users with Project Manager or Organization Admin permissions.
If needed, it is possible to edit a set ID or renumber items in a set at any time. To do this, right-click on the set you'd like to modify and select Change set key.
This will open a pop-up window where you can enter a new set key.
To apply the new set key numbering to all existing items, check Regenerate item IDs. This will reset all the Unique IDs, and the item counters number will start over at 1.
If you want to restart numbering on newly created items and leave existing items as they are, do not check Regenerate item IDs.