ajp port override not working

[honnuanand]

I am setting the ajp port as below .. but still get the error :

> Task :uaa-server:cargoRunLocal FAILED
org.codehaus.cargo.container.ContainerException: Port number 8009 (defined with the property cargo.tomcat.ajp.port) is in use. Please free it on the system or set it to a different port in the container configuration.

build file :

cargo {
    containerId = 'tomcat8x'
    port = 8090

    deployable {
        file = file("$buildDir/cloudfoundry-identity-uaa-${uaaVersion}.war")
        context = 'uaa'
    }

    local {
        containerProperties {
            property 'cargo.tomcat.ajp.port', 9099
        }

        outputFile = file("$buildDir/uaa-server.log")
        installer {
            installUrl = 'https://www-us.apache.org/dist/tomcat/tomcat-8/v8.5.34/bin/apache-tomcat-8.5.34.zip'
            downloadDir = file("$buildDir/download")
            extractDir = file("$buildDir/extract")
        }
        systemProperties {
            property "UAA_CONFIG_PATH", "$projectDir"
        }
    }
}