Apply the same changes to many contacts

curl -X POST 'https://api.expiryedge.com/v1/bulkUpdateContacts' \
  -H "Authorization: Bearer $EXPIRYEDGE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "contactIds": [
    "c_8Hk2pQ",
    "c_3Rm7vN"
  ],
  "updates": {
    "contactGroup": "Vendors",
    "sendNotifications": true
  }
}'

{
  "success": true,
  "updated_count": 2,
  "updated_ids": [
    "c_8Hk2pQ",
    "c_3Rm7vN"
  ]
}