Validate an SMS campaign

curl -X GET 'https://www.unitpost.com/api/v1/sms/campaigns/cmp_123/validate' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'User-Agent: my-app/1.0'

{
  "object": "sms_campaign_validation",
  "campaign_id": "campaign_123",
  "can_send": false,
  "blockers": [
    {
      "code": "string",
      "message": "string"
    }
  ],
  "total": 1,
  "reachable": 0,
  "skipped": 0,
  "no_marketing_consent": 0,
  "quiet_hours_deferred": 0,
  "skipped_by_reason": [
    {
      "reason": "string",
      "count": 1,
      "remedy": "string"
    }
  ],
  "routing": "automatic",
  "earliest_start": {
    "at": "string",
    "reason": "quiet_hours",
    "countries": [
      "string"
    ]
  },
  "use_case_mismatch": false,
  "unresolved_variables": [
    "string"
  ]
}