Failed transaction but money deducted from bank account

I made a payment to a merchant on Saturday and the payment failed on the merchant's website but the money was deducted from my bank account. The merchant has allegedly contacted Peach payments but has not received a response from them. The money has still not been returned to my bank account or the merchant's account. I understand that glitches can happen but not responding to queries is appalling. I would advise merchants and consumers not to make use of this payment platform.