Thanks for reaching out on the Community. We hope you don't mind us helping you in English, since this is the official Community language :)
Could you try reactivating your student discount via the confirmation email that you should have received in your inbox? In case you didn't get it, just head over here. To make sure you were able to activate it succesfully, have a look at your subscription status here.
If you would like to get a refund, you should get in touch with our Customer Support team here, who will be able to do that for your provided you are eligible for one.
Hope that helps! Let us know if you need any further help with this.
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