Hi srirangam mishra,
Thank you for reaching out to us on the Microsoft Q&A forum.
When you receive additional Azure credits, such as an upgrade from $5,000 to $25,000, any unused credits from the previous allocation do not carry over. For instance, if you utilized $3,000 from your initial $5,000 credit, the new $25,000 credit allocation begins afresh, and the previous usage does not impact the new balance.
Regarding your support plan, certain Azure credit offers include support plans such as Standard or ProDirect. It appears that your current plan is ProDirect, which is a higher-tier support option. Unfortunately, the available documentation does not provide specific guidance on downgrading to a Basic plan. To make changes to your support plan, we recommend reaching out to Azure Support directly through the Azure portal or you please create a support ticket with the billing team here. They will be able to assist you in resolving this matter efficiently.
Please reach out to us if you have any other queries.
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