how can we get the log in history of our account ?

If the NAB will not provide you with the access information regarding the account, then I recommend you make a complaint about this to the Financial Services Ombudsman. Simply call the Ombudsman's office on (03) 9613 7366 and tell the person who answers that you want to "Lodge a Dispute". Be sure to use those words, or they may send you to the incorrect department.

The dispute department will ask you to fax or email or post to them a letter detailing what happened, what action you took to resolve this problem with your bank, and lastly, why you feel aggrieved. If you don't want to write this all down, you can explain it to the person on the phone who can take down all the relevant details, but that of course, could take a while to explain it all. Once the Ombudsman has the written complaint, they will investigate. The Ombudsman aims to resolve every dispute within forty five (45) days.

I have used their service myself on occasion, with amazing results. If the Ombudsman agrees with you, they have the power to make the NAB give you the account log in records. So that would be the best course of action for you to take here.

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