Terrible Service & Terrible Pricing
First of all, the website doesn't tell you ANYTHING other than to give you their contact details and that they deal with Wallbox chargers.
I got an electric car because we had a Wallbox pre-installed in the underground parking in our apartment complex. The agency we rent from told us that e-wallbox.de is responsible for dealing with the chargers.
They are not just Wallbox installers though, they have their own electricity contracts.
They charge you close to 9 Euros per month for just having the contract with them in the first place. If my math is correct, that's enough to charge 22 kW/hr to your car. I can easily go over 100 KM with that charge even for a car with poor efficiency. That's a 100 KM range you're giving away for free. Not to mention that their charging tariff is not much cheaper than the public chargers.
There is no option to sign a contract with another electricity provider or use your own electricity provider. Not something that is shared ahead of time and obviously not on their website.
This is classic backroom deal-making so they're the only monopoly and leave you no option but to go with their ridiculous contract.
Oh, and the minimum term is 12 months for the contract, which you have to wait 30 days to have them activate the charger, and if you forget to cancel it after 12 months, it gets extended another 12 months. So yeah, it's terrible!