I was asked to upload my A1/A3 license in a better quality. How do I do this?

Ideally, you should simply upload the PDF file that you received from the Luftfahrt-Bundesamt or your local aviation authority. If you want to take a photo of your physical license, make sure to take the photo in as much light as possible, preferably outside.

You then simply send the PDF file or photo to [e-mail] with the text "A1/A3 license of [first name] [last name]". The text is important because an empty email with only an attachment usually ends up in SPAM.