Go to this web page: https://backoffice.bsport.io/login and log in with your email and password.

Once logged in, click on 'Subscription'. A notification appears to inform you that you have a subscription without payment method yet.

Click on "Modify" to change your payment method or on "Add" to fill it in.

Fill in the payment method information

Click on the saved payment method to highlight it and click on 'Bill'.

Your subscription will now be billed on with this payment method.