Hi Ashesh,
Yes, v3 has been deprecated for a while. You should have received several e-mails from our product team regarding migration, please make sure you read them.
If you don't have access to the e-mail account then get in touch with your account manager or point of contact
Cheers,
Jose
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Jose Alcérreca
Developer Relations
Google UK Limited
Registered Office: Belgrave House, 76 Buckingham Palace Road, London SW1W 9TQ
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