https://www.bunnings.com.au/brunnings-500g-wasp-and-ant-dust-puff...

https://www.bunnings.com.au/brunnings-500g-wasp-and-ant-dust-puffer-pack_p3010439

i had a bulldog ant nest near my house a while back not sure if its the same ants you have but i sprayed every guard i came across then sprayed all around the entrance then got a couple of sprays down the hole after i managed to get past the guards and it did the trick, the powder needs to be used only when its dry and any rain a day or so after using it will probably make it ineffective too