Debit account without authorisation

Frustration without words. Who authorised the debit order to go through? You guys embarrassed me last week friday where i stood at a counter and could not purchase anything but you guys confirm that i can purchase for an x amount and then there is arrears where ive made all the arrangements to get it up to date, now your story is this and that the bottom line is why take an payment knowingly that the client cant purchase due to arrears why dont you inform me about that? Wake up please you guys are terrible. On my previous complained i said do not debit my account as you guys dont know whats going on and here you go and debit my account without authorisation. Ill have to log a complaint further on this.