Install Prometheus AlertManager from https://prometheus.io/download/ and create configuration as below

```yaml
route:
  group_by: ['alertname']
  group_wait: 30s
  group_interval: 5m
  repeat_interval: 1h
  receiver: 'web.hook'
receivers:
  - name: 'web.hook'
    webhook_configs:
      - url: 'http://127.0.0.1:8010/webhook'
inhibit_rules:
  - source_match:
      severity: 'critical'
    target_match: