Click on the transaction in the transaction history. Select "Add category" and then choose a category from the list.
You can change the category again just as easily. Click on the icon next to the payment and change the category.
If you have any questions about this topic, our customer service will be happy to help you from 9:00 to 18:00 on weekdays by phone at +49 30 255 585 803 or by e-mail at firstname.lastname@example.org.