I have a student account but Adobe started charging me full price
Let me move this to the Account, Payment, & Plan forum for you, which is the appropriate forum for your question.
The Using the Community forum is for help in using the Adobe Support Community forums, not for help with specific programs. Product questions should be posted in the associated product community.
If you've had your subscription for more than a year, the first year discount has expired. You're probably still being charged the student rate but it's the full student rate instead of the discounted one. That or you need to reverify that you're still a student.
In either case, this is a public forum, not Adobe support. Users, including the ACPs and MVPs, can't provide support for account, subscription, billing, download, or product activation issues. Support for those issues requires an Adobe employee.
Adobe provides support through the Chat function on the contact page or through a phone call. There is no email support.
CHAT: Click the following to contact Adobe customer support staff for help:
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Click the chat icon at the bottom right of the page to open a chat session.
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The student price is USD $19.99/mo for the first year only. After that it goes up to $29.99/month.
Why is this? I feel that it is not clear when signing up for the subscription that the student price increases after one year. Do I have the opportunity to get a discount again? I don´t whant to continue my subscription if I am not able to get a discount.
No, you get that special discount on the normal price only in your first year.
I'm not sure which part of this isn't clear.
Not only that, but $29.99 is a discount from the regular subscription price, which is $52.99 per month.
It's just a 40% discount instead of a 60%.
It used to be that the student price for Creative Cloud was always a 40% discount, or $29.99/month. The regular price was $49.99/month.
Then, in 2015, Adobe dropped the price of the first year of the Student/Teacher Edition even further, to 60% off, or $19.99/month. Originally this was a limited-time offer, but then they made it available for all new education customers.
So there's still an academic discount – and always has been – it's just a matter of how much.