Hey there folks,
Thanks for posting about this here in the Community!
We hope you don't mind us replying in English as it's the Community's official language.
Our student discount expires after a year, after which your subscription automatically continues at the standard monthly rate.
If you're currently experiencing this, you can reapply the discounted rate on your account provided you're still eligible for the discount.
Keep in mind that it's only possible to reapply the student discount a maximum of 3 times, covering a total of 4 years.
For more information on Premium for Students we'd suggest taking a look at this support site article.
Hope this helps clarify things! If there's anything else we can help with, don't hesitate to give us a shout in the related Help Board. We'll be happy to lend a hand there.
Have a lovely day :)