Here's the deal with the DHL code: the mobile app doesn't have a field to enter a discount code (at least not that I can find).
- If using the mobile / tablet app, go to https://mydhl.express.dhl/index/en.html and choose Germany as your country.
- Hold down the formatting button (see screenshots for examples of Safari on iOS and Chrome on Android) and choose 'Desktop Website.'
| Android | Apple |
 |
 |
- You'll get the version of this page that runs on a laptop or desktop (or possibly a large tablet). It's hard to use on a small screen, but you get different options, including being able to input a discount code at the end. See the screenshots below for details.
| Android | Apple |
 |
 |