@Deepika Nayak Thank you for reaching out to us, As I understand you want to disable Ipv6 for your specific tenant ? As far I know Ipv6 is enabled at the service level (Azure AD), let me check if there is an option to disable the same for specific tenant or not.
Our service endpoint URLs resolve to return both IPv4 and IPv6 addresses, If a client platform or network supports IPv6, the connection will mostly be attempted using IPv6, assuming that the network hops that are in between (such as firewalls or web proxies) also support IPv6. For environments that don't support IPv6, client applications will continue to connect to Azure AD over IPv4.
In your scenario, firewall doesnt support IPv6. Its not possible for us to disable ipv6 for specific tenant.
Let me know if you have any further questions, feel free to post back.
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