Statement and Sms balances does not correspond

Im very upset by how nedbank displays their account balances via the sms system.On the 22 Des2017 I made several purchases at various retailers.I swiped my debit card to pay.for the purchases.After each transaction on that day I received an sms which displayed my purchase amount and also my available balance.Thus confirming that the amount I have left in.my account is still available..On the 28 there was an amount available in.my acc which I withdrew on the same day..However..after that I received an sms saying my acc is in debit of R 417.So which means if any cash was deposited it was suppose to rectify the debit balance...On 5 Jan.2018 an.amt of R 524 was paid into my account but the balance remained negative...Now my.question is..after each transaction where the purchases was deducted and money was available,how is it possible that my account went into debit?And also the sms shows that on.the very same day of the purchases that.the money was also deducted from my account.My statement from the branch differ from the sms system.statement...This is really upsetting because according to me when my balance was negative and funds was transfered into my account on the 5th of Jan..should that negative balance not be cancelled?I couldnt get much help via telephone banking nor at the branch...Im a new nedbank customer and I personally think their internet system or whatever systems is a waste of time..I cant even activate my mobile banking due to service errors...The system.is more offline then available.