Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
I can advise you as to what to do, if you will tell me what seller you wish to use direct debit with.
If that seller is online, then either you would have to special order through that seller's Customer Service line, or else, if their online facilities allow it, to present payment through their online facilities.
Tell me which seller it is, and I will give you further specifics.
If that seller simply does not accept direct debit, you may have to arrange to have direct debit pay to another account that they do accept, such as the Paypal.com service for instance, whose direct payments many online and website-based sellers accept. If this is needed I can instruct you in detail as to how to do so.