@Kean Hin Gunn Apologies for the delay in response and all the inconvenience caused because of the issue.
The Microsoft Azure Premier Plan has been built to accelerate your cloud adoption journey through a complete coverage for cloud, hybrid, and on-premises solutions across all Microsoft products
The Premier Support plan is part of the “Enterprise support offering” includes personalized hand-on assistance and training to maximize your return on investment; as well as a dedicated Technical Account Manager who can drive pro-active support for all your Business solutions (including non-Microsoft Applications).
In order to create Support Request users first need to be an Owner, Contributor or be assigned to the Support Request Contributor role at the subscription level. Not every user can create a Support Request and it solely depends upon permission provided to user by Admin since alot of cost is included as well.
You can refer to this documentation to understand how to create Support Request in Azure portal irrespective of Support Plan. Only plan it won't be applicable is CSP plan where there are dedicated partners who can open Support Request.
Hope it helps!!!
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