Azure Container App Job on a event trigger executes every pooling interval instead of when a new message arrives in queue

Question

I have a container app job with an event trigger that should only execute when a new message is in a blob storage queue. However it executes on every pooling interval (i have set it to 5 minutes), which just consumes additional resources without processing anything. Below is my JSON configuration of the job:

{
    "id": "***",
    "name": "***",
    "type": "Microsoft.App/jobs",
    "location": "East US",
    "properties": {
        "provisioningState": "Succeeded",
        "environmentId": "***",
        "workloadProfileName": "Consumption",
        "configuration": {
            "secrets": [
                {
                    "name": "connection-string-secret"
                },
                {
                    "name": "***"
                }
            ],
            "triggerType": "Event",
            "replicaTimeout": 4000,
            "replicaRetryLimit": 1,
            "manualTriggerConfig": null,
            "scheduleTriggerConfig": null,
            "eventTriggerConfig": {
                "replicaCompletionCount": 1,
                "parallelism": 1,
                "scale": {
                    "minExecutions": 0,
                    "maxExecutions": 2,
                    "pollingInterval": 300,
                    "rules": [
                        {
                            "name": "queue",
                            "type": "azure-queue",
                            "metadata": {
                                "accountName": "***",
                                "queueLength": "1",
                                "queueName": "***"
                            },
                            "auth": [
                                {
                                    "secretRef": "connection-string-secret",
                                    "triggerParameter": "connection"
                                }
                            ]
                        }
                    ]
                }
            },
            "registries": [
                {
                    "server": "***.azurecr.io",
                    "username": "***",
                    "passwordSecretRef": "***"
                }
            ],
            "dapr": null
        },
        "template": {
            "containers": [
                {
                    "image": "***.azurecr.io/***:latest",
                    "name": "***_job",
                    "env": [
                        {
                            "name": "AZURE_STORAGE_QUEUE_NAME",
                            "value": "***"
                        },
                        {
                            "name": "AZURE_STORAGE_CONNECTION_STRING",
                            "secretRef": "connection-string-secret"
                        }
                    ],
                    "resources": {
                        "cpu": 4,
                        "memory": "8Gi"
                    }
                }
            ],
            "initContainers": null,
            "volumes": null
        },
        "eventStreamEndpoint": "***"
    },
    "identity": {
        "type": "None"
    }
}

Any ideas why this could happen? Thanks in advance!