Unapprived debit order after everything was cancelled

I cancelled everything that the guy sold me cause I thought it was for a loan and I never approved the debit order on my banking app for the debit order to go off I have received messages that the plans was cancelled but still the debit order went off today. I want my money refunded to me and a written email stating that everyting is cancelled!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!