@Zar Ni, Thanks for posting in Q&A.
From your description, I know you cannot join Azure AD in Myanmar country.
To clarify this issue, please check the following.
Can you clarify for us whether by Azure Cloud AD you mean Azure Active Directory (now renamed Microsoft Entra ID) or Azure Active Directory Domain Services?
Moreover, please also share with us if there are any errors or tips that you're getting when you join Azure Cloud AD.
If there is any update, feel free to let me know.
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