@AnuragSingh-MSFT - Thanks for reaching out to us.
To resolve this issue, consider using a logic app to generate a custom payload in the email, which can include the desired details such as recovery vault names. You've successfully created V1 alerts using the API method and are exploring customizing V2 alerts with logic apps.
Please take a look at this doc for more reference
Hope this helps. and please feel free to reach out if you have any further questions.
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