From the bitcoin.de FAQ:
As soon as you have created a sales offer at bitcoin.de, the respective amount of Bitcoins is marked as reserved balance and cannot be used for any other sales.
If a buyer was found, the seller can no longer have the operator disburse the sold Bitcoins.
The Bitcoins remain blocked for the seller as well as for the buyer until the buying process is completed;
To be found here:
https://www.bitcoin.de/en/faq/what-does-bitcoin-de-do-to-offer-security-to-buyers-and-sellers/39.htmlAccording to their FAQ, btc's are only marked as reserved when there is an sell order open.
Is it possible you accidentally created a sell order, which hasn't been fulfilled yet? Not sure why they don't show up in your screens.
Its quite strange you don't see any sell orders. I think the only one able to help you in this case is the support of bitcoin.de
I have used that site before and when your coins are seen as "reserved" it means that you've sold them but haven't released the payment
In such a case it should mark the coins as
blocked, not reserved.
Everything is fine with the TX. It got confirmed >1 month ago.