Hello bist17,
Can you check with below query and revert me.
SELECT [vc].[Guid],
vc.Name AS 'Computer Name',
vc2.Name AS 'Task Server Name',
vs.Name AS 'Site Name'
FROM [vComputer] AS [vc]
INNER JOIN [Inv_AeX_AC_TCPIP] AS [tcp] ON [tcp].[_ResourceGuid] = [vc].[Guid]
INNER JOIN [vSite] AS [vs] ON [vs].Name LIKE '%'
INNER JOIN [vSiteSubnetMap] AS [ss] ON [ss]._ResourceGuid = [vs].[Guid]
INNER JOIN [Inv_Subnet] AS [sn] ON [sn].[_ResourceGuid] = [ss].[SubnetGuid]
INNER JOIN [Inv_Client_Task_Resources] ctr on ctr._ResourceGuid = vc.Guid
INNER JOIN vComputer vc2 on vc2.Guid = ctr.ClientTaskServerGuid
WHERE
dbo.[fnIsIPInSubnet2]([tcp].[IP Address],[sn].[Subnet],[sn].[Subnet Mask]) = 1
And plz check HighTower post in below thread,
https://www-secure.symantec.com/connect/forums/queryreport-show-what-site-pc-belongs