nextflow cluster profile not found?

bash-4.1$ nextflow run brainstorm/bwa-nextflow-benchmark -with-timeline timeline.html -with-trace -with-dag flowchart.png -profile cluster
N E X T F L O W  ~  version 0.24.0
Launching `brainstorm/bwa-nextflow-benchmark` [amazing_cori] - revision: 9cc871964a [master]
Unknown configuration profile: 'cluster'
bash-4.1$ cat nextflow.config
manifest {
    homePage = 'http://umccr.github.io'
    description = 'BWA AWS vs NCI test'
}

aws {
	region = 'ap-southeast-2'
}

standard {
    process.executor = 'local'
}

cluster {
    process.executor = 'pbs'
    process.queue = 'normalexpress'
    process.memory = '8GB'
}

cloud {
	imageId = 'ami-f3dfdd90'
	instanceType = 't2.small'
	bootStorageSize = '10GB'
	userName = 'ubuntu'
	/* process.executor = 'k8s'
	   spotPrice = '1.8'
	*/
}