Hello Handian Sudianto,
Thanks for your question.
This may require creating a ticket or contacting Azure support as I also checked and saw the IP from biznet networks in IND. You might also need to contact the ISP to see if they can help.
As a temporary measure, maybe modify the Conditional Access policy to allow access from the specific IP address before support gets to it?
You can mark it 'Accept Answer' and 'Upvote' if this helped you
Regards,
Abiola