PSA about Vodafone prepaid SIM for tourists: bad deals that don’t match website and no way to reload via app

I got a Vodafone SIM card in Frankfurt, Germany recently. Came looking for the 15 GB for 20€ option advertised here: https://www.vodafone.de/privat/handys-tablets-tarife/prepaid-ohne-vertrag.html

But instead, the options I had were 15€ for 6 GB or 20€ for 9 GB, with an additional 20€ fee for the SIM card on top of that. Very different from what was advertised on the site.

Maybe it’s an online-only deal, who knows. What makes it worse is that (a) the Android Vodafone app won’t even let you type in the phone number, and (b) the iPhone app doesn’t recognize the number either, so I can’t reload the SIM.

Would advise *against* Vodafone prepaid SIMs for tourists.