Hi @Gooi Han Yan
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
If your Azure Cosmos DB subscription is suddenly disabled, it may be due to various reasons such as reaching your spending limit, an expired credit, or other account-related issues. Since you mentioned that you are unable to reactivate the subscription due to authorization issues, it is important to check if your account meets the requirements for accessing the Azure Cosmos DB service.
For a Try Azure Cosmos DB subscription, it is specifically noted that account access can only be granted to personal Microsoft accounts. If you are using a Microsoft Entra account or a corporate account, this could lead to access issues.
If you have any concerns, please go through this link: -
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/subscription-disabled
https://learn.microsoft.com/en-us/azure/cosmos-db/faq#try-azure-cosmos-db-free
If you have any further queries, do let us know
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