Disputing a credit card transaction

I just found a strange charge of $554 to WA Dept of Transpot and I'm in QLD. I decided to dispute it with CBA - but they only have the nuclear option - cancel my card, and get a new one.

Is this your experience trying to dispute a transaction?

As for their ai chatbt CEBA - it refuses to connect me to a human, insisting that I have to cancel the card.