slack notify retry canceled due to unrecoverable error 403

[johirulalam]

ts=2024-02-18T18:53:00.366Z caller=dispatch.go:352 level=error component=dispatcher msg="Notify for alerts failed" num_alerts=1 err="slack-notifications/slack[0]: notify retry canceled due to unrecoverable error after 1 attempts: channel "#monitoring": unexpected status code 403: invalid_token"

alertmanager.yml
global:
slack_api_url: 'https://hooks.slack.com/services/T06L1G****'

route:
receiver: 'slack-notifications'

receivers:

• name: 'slack-notifications'
  slack_configs:
  • channel: '#monitoring'

Rules

groups:

• name: os
  rules:

  • alert: NodeExporterDown
    expr: up{job="node_exporter"} == 0
    for: 15s
    labels:
    severity: critical
    annotations:
    summary: "Node Exporter is down"
    description: "Node Exporter is down for more than 2 minutes"