curl --request POST \
  --url https://{cluster}.voucherify.io/v1/loyalties/{campaignId}/members \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'X-App-Id: <api-key>' \
  --header 'X-App-Token: <api-key>' \
  --data '{
  "customer": "source_customer_1",
  "metadata": {
    "year": 2022
  },
  "channel": "postman",
  "voucher": "KpzbHUY5"
}'

{
  "id": "v_0TxKw1bm0oZuS5lwA8526vze1OBMV1OH",
  "code": "KpzbHUY5",
  "campaign": "Loyalty Campaign",
  "campaign_id": "camp_eTIsUtuzkRXQT6rsUQqrS5Gw",
  "category": "New Customers",
  "category_id": "cat_0b6152ce12414820dc",
  "categories": [
    {
      "id": "cat_0b6152ce12414820dc",
      "name": "New Customers",
      "hierarchy": 0,
      "created_at": "2022-07-14T20:17:07.657Z",
      "object": "category"
    }
  ],
  "type": "LOYALTY_CARD",
  "discount": null,
  "gift": null,
  "loyalty_card": {
    "points": 0,
    "balance": 0
  },
  "start_date": null,
  "expiration_date": null,
  "validity_timeframe": null,
  "validity_day_of_week": null,
  "active": true,
  "additional_info": null,
  "metadata": {
    "Season": "Fall"
  },
  "assets": {
    "qr": {
      "id": "U2FsdGVkX1+hdZfzUaz448vIsyf7WpvXiDyqFbyw0+P5wMu12w3B5DyYwA7LCSK+Nr7TA7PKGuHOTGxfBieqrhvJo81HiaIJimDOhk+ecEOisMRmHf6XsNckVlyBHmkpBiXWNm8UDwZnXOAG75Usdw==",
      "url": "{{internalVoucherifyURL}}"
    },
    "barcode": {
      "id": "U2FsdGVkX19VRXApVvZ9/ArwBd0wNg7s2KZBXrFvPXZdDQyzGj0HbbEIx5TAoXNR9zaE5kzIj9BElzgK82aOMMVnc1sqvr93xw+YeYMnqGqHRZfM78pYC8560Zc3U6IELtxzaJJ0x2uDUe6Dc9XYeg==",
      "url": "{{internalVoucherifyURL}}"
    }
  },
  "is_referral_code": false,
  "created_at": "2022-11-21T15:48:57.860Z",
  "updated_at": "2022-11-21T15:49:36.671Z",
  "holder_id": "cust_8KQmHxAERpgebYcFhSpZRr37",
  "redemption": {
    "quantity": null,
    "redeemed_quantity": 0,
    "redeemed_points": 0,
    "object": "list",
    "url": "/v1/vouchers/KpzbHUY5/redemptions?page=1&limit=10"
  },
  "publish": {
    "object": "list",
    "count": 1,
    "url": "/v1/vouchers/KpzbHUY5/publications?page=1&limit=10"
  },
  "object": "voucher"
}