@Maria - Thanks for the question and using MS Q&A platform.
Firstly, it's important to note that when a subscription expires, all resources associated with it are deleted. This means that your old workspace and files would have been deleted when your student subscription expired.
However, there may be a way to recover your files if you had backed them up or exported them before your subscription expired. Did you happen to export your notebooks or files before your subscription expired? If so, you can import them into your new workspace.
If you did not export your files, unfortunately, there may not be a way to recover them.
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