@Marie-Louise Øgendahl Andersen (EAAMLOA) Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
I would recommend to contact Azure Billing and Subscription team would be the best to provide more insight and guidance on this scenario:[ https://azure.microsoft.com/en-us/support/options/] Free support is been provided.
Change your Azure subscription to a different offer
Details on Azure for Students subscription
Additional information : At the end of your first 30 days or after you spend your USD200 credit (whichever comes first), we'll ask you if you want to move to pay-as-you-go pricing. If you move to pay as you go, you'll keep getting free services and you'll only pay for what you use beyond the free monthly amounts. If you don't move to pay as you go, you can't purchase Azure services beyond your USD200 credit—and eventually your account and services will be disabled.
*What happens once I use my USD200 free credit or I am at the end of 30 days?**We will notify you so you can decide if you want to move to pay-as-you-go pricing, enabling you to purchase Azure services beyond free amounts. If you do, you will keep getting access to all the free services. If you do not, your account and services will be disabled. To resume usage, you will need to move to pay as you go.
For more information refer to Azure Free account FAQ
Please let us know if you have any further queries. I’m happy to assist you further.
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