Domain Deletion error in WIn 2003 Plesk Control Panel 6.5.1

[arbinfosys]

we are using https://house4domains.net reseller control panel of win 2003 server with Plesk 6.5.1 Control Panel.Whern we try to remove/delete exited domain ,we receive error ' unable to remove domains.You do not have the permission to remove domain domainname.com