sounds like below. if this is what we want please post some sample data from tables and explain what you want with required output
UPDATE v
SET v.ORG = b1.ORG
FROM VoipNumbersMonthly v
INNER JOIN [Tesisdev].[dbo].[BillingORG] b1
ON b1.[bnumber] = v.[bnumber]
INNER JOIN
(SELECT bnumber, MAX([activedate]) AS Date
FROM [Tesisdev].[dbo].[BillingORG]
group by bnumber)b2
ON b2.bnumber = b1.bnumber
AND b2.[Date] = b1.[activedate]
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SQL Server MVP
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