Thanks for getting in touch! We hope it's okay if we reply in English.
It's important that you get verified as a student before the money is withdrawn from your bank account. Also make sure you subscribe with the account that has been verified. It's easy to create an account with us so it can happen that users have a second account they do not know about. You can read here how to find any extra accounts you might have.
Should help! Let us know if you have further questions.
If you received an email, did you verify that you're a student from there? There should be an option or a button that you need to press. If that has already been done, or you don't see that option, please get back to us with a screenshot of the email. Make sure you hide any personal info such as the full email address and full names.
Before you do that, open the Student Discount page in an incognito window and try signing up again. What happens when you do that? Don't worry about any double charges, it always makes sure you only pay once per month if you've already completed a transaction.
Lastly, we suggest that you check out your bank/PayPal statements. If you find any discounted charges that appear to be pending, it means that the verification process of your student details is still ongoing, and you'll have to wait a bit more.