Disappointed with Nedbank. On-line purchases not secure

I made a purchase on-line for the amount of R70 however without a confirmation or sms sent to the phone, to approve of the transaction ,and amount, R1928,61 was deducted without me being able to stop it. I was under the impression that it is a SA company, however only to find that it is not and there is also a cross border fee. The bank should not allow transactions to go through without an ATP or pin sent to my phone. Myself as well as my husband tried to stop the people ( Strandcareinfo.com ) from getting the money. I phoned the bank immediately after seeing that R1928,61 is being deducted. I was told to complete a dispute form and send it to the bank. This I did but I am now told that it takes 3 weeks for an answer. At the bank I am told that not al merchants are secure. How am I supposed to know that. Nedbank is supposed to protect me from ************ merchants. In the past it has always been a pleasure to buy on line , as a code is sent to me and I can either continue or cancel the transaction. We have asked the bank to place security on our cards by letting NO transactions through without a pin.however this seems to be impossible according to the person at their ***** dept.