@tkrajeesh , you can query for the list of savesets using mminfo or from the NetWorker Administrator console. Then create a script using nsrmm to expire those savesets. Give it a day or run nsrim -X manually and you should see the space available. keep in mind DD is a dedupe based system so the amount of data cleared/delete will not be same as the data made available on the DD.

Hi @tkrajeesh 

Try this https://www.dell.com/community/NetWorker/How-to-free-space-on-Data-Domain-for-allready-deleted-save-sets/m-p/7749304