Hello Shubh,
the supply chain unit is still used in one or multiple deliveries in EWM. Therefore it can not be deleted as otherwise this information would be missing in the delivery.
The supply chain unit can be maintained in transaction /SCMB/SCUMAIN.
Is your SCU assigned to a warehouse? You can check in table /SCWM/T300_MD. Then it will most likely be part of deliveries.
You can e.g. check in table /SCDL/DB_BPLOC an enter you SCU in field LOCATIONNO to see in which deliveries it is used (there are also some othre database tables, but this is the most likely how to find the corresponding deliveries).
Best regards
Markus
