Debit order penalty

Bad service their consultants they Don, t know what they are doing sign up for a contract put the 20th for the deduction date they put the the debit order for the 31st I payed them then still they deducted my money now they say I owe they the money for the debit order reversal who is at fault me or them now they take me from pillar to post the lady by the name of sfundo Sindane I have been waiting for the feedback ever seen. Was not even my fault my form stated the deduction date for the 20th because I get paid on the 20th.