Unarranged debit causing damage to my credit

They debited my account three days before the agreed date. Putting my account into overdraft which can mess up my budget and debit orders. When I enquire about it, they just said they sent an sms for me to approve that arrangement which I didn't because I signed a contract for 15th of every month where would i get money on the 12th? On top of that the salary day does not fall on a weekend it is on Monday so why do they rush to debit the money? This is a serious violation of my human right, and seeing by their reviews it seems they do have some work to do on themselves. This is unacceptable and really depressing.