Help with interest rate

Hi friends, just coming off our home loan which was a sweet 3.59% we fixed for 3 years when buying, exactly two weeks before interest rates started to rise.

Now the time has come that we are moving off our rate onto variable and this is what ANZ is offering.

We bought with a 0% deposit as my MIL offered to go guarantor with her home.

We unfortunately overpaid for our home when we bought it in 2022 and I believe our LVR is terrible because according to realestate.com our home is now worth less than what we bought it Bought for 552k home is now worth 546k. Still have 540k remaining on the loan.

So essentially How can we get a better rate? Can we? Or do we have to suck it up and pay the extra 1k a month. (Going from $2500 to $3600)

This is what ANZ is offering

6.74%?