How to treat Sir Walter Buffalo lawn going brown?

[Barry7]

I had Sir Walter Buffalo laid approx. 10 months ago and it was doing very well. In the last 2 weeks, large areas look like they are dying - see photo below. Any assistance/thoughts would be welcome. Area close to fence still looks OK/normal, but rest is brown?

[Barry7]

Thanks - this looks like it is more eco and dog friendly....https://www.bunnings.com.au/multicrop-2l-ecogrub-3-in-1-insecticide_p2961324 

[MitchellMc]

Yes, it would be, @Barry7.

Mitchell