You should consider that direct debit as a payment method needs an activation process of about 7-14 days. Therefor you won’t be able to use direct debit without completed activation process.
Please note too that this service is only available in Germany right now!
EDIT: checking the terms of service fine printed at the bottom of the page I finally found this
3.1 The merchant receives the right of use to the Paymill platform limited to the duration of the contract,
territorially restricted to the following countries, which is non-exclusive, non-sublicensable, non-transferrable and non-assignable. Countries in scope: Andorra, Belgium, Denmark, Germany, Estonia, Faroe
Islands, Finland, France, Greece, Ireland, Iceland, Italy, Israel, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Netherlands, Norway, Austria, Poland, Portugal, Sweden, Switzerland, Slovakia, Slovenia,
Spain, Czech Rep., Turkey, UK, Hungary, Cyprus (Greek part), Vatikan City (State). The right of use is valid
for access to the platform via the Internet and for use of the functionalities associated with the Paymill
platform in accordance with the regulations of this contract and the documentation. The merchant shall
be entitled to use the documentation solely for the connection of the utilized data processing system to
the Paymill platform and to store the data transmitted to the merchant via the Paymill platform on its
data processing system or a data processing system of a third party authorized by the merchant.
The down-votes come because you assert a fact that is incorrect and can meaningfully impact the supplier and folks reading here. Perhaps "It looks like PayMill is Germany only?" is a better approach.
You should consider that direct debit as a payment method needs an activation process of about 7-14 days. Therefor you won’t be able to use direct debit without completed activation process. Please note too that this service is only available in Germany right now!
EDIT: checking the terms of service fine printed at the bottom of the page I finally found this
3.1 The merchant receives the right of use to the Paymill platform limited to the duration of the contract, territorially restricted to the following countries, which is non-exclusive, non-sublicensable, non-transferrable and non-assignable. Countries in scope: Andorra, Belgium, Denmark, Germany, Estonia, Faroe Islands, Finland, France, Greece, Ireland, Iceland, Italy, Israel, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Netherlands, Norway, Austria, Poland, Portugal, Sweden, Switzerland, Slovakia, Slovenia, Spain, Czech Rep., Turkey, UK, Hungary, Cyprus (Greek part), Vatikan City (State). The right of use is valid for access to the platform via the Internet and for use of the functionalities associated with the Paymill platform in accordance with the regulations of this contract and the documentation. The merchant shall be entitled to use the documentation solely for the connection of the utilized data processing system to the Paymill platform and to store the data transmitted to the merchant via the Paymill platform on its data processing system or a data processing system of a third party authorized by the merchant.