CarTrack Cannot change Debit Order dates

Car Track cant change debit order dates even with advanced notice. Due to job change I need to change all my debit orders to 3 days later that it is currently set to. Iven though I have given them 3 and a half weeks notice they advise that they cannot change the Debit order untill next month. This is proposterous as I have not had any other company give this requirement while changing 14 other debit orders. Then to crown it they say thew will charge over R100 if I wish to cancel the service because of their inadiquecies. This is not acceptable.