Amit, do you mean that the RPM version includes a file where the DB user is set to 'nsadmin'? If so, which file and which line of that file? Or do you mean you edited a file to do this?
If I've left an instance of 'nsadmin' (is that really the recommended PG username) somewhere it shouldn't be, I'll very gladly change it to acs so things work better 😊