I wonder if its a continuous payment authority. From vanquis website:
What is a Continuous Payment Authority and how do I set one up?
A continuous payment authority, a ‘CPA’, is a form of regular payment, where you provide us with your current account details and authorise us to request payments from that account.
As part of the application process for the Vanquis Bank Visa Card, we may ask you to set up CPA on a payment account of yours (such as your current account). Should your application be successful, we will use the CPA to request payments from that account in respect of the repayments due each month on your Vanquis Bank Visa Card Account. You will be able to specify the amounts to be collected from your payment account along with the date those payments are to be collected (which should be the date by which your repayments should reach your Vanquis Bank Visa Card Account in each month). You can also set up a CPA at any time after your Vanquis Bank Visa Card Account is opened.
We will collect repayments of the specified amount using your CPA until you tell us to stop which you can do by calling or writing to us. You can also cancel your CPA by telling your payment account provider. If you cancel your CPA, you will still have to pay at least your minimum payment due by the payment due date. For details of other ways you can make payments on your Account can be found below.
If you have insufficient funds in your payment account and we are unable to collect the repayment under the CPA we will try to take it once more, on the next working day. If we are unable to collect a repayment under the CPA we will advise you of this.