Why are transactions duplicated in Analytics?

Question

Google Analytics

Greetings!
Help, please, to understand.
In analytics, orders are periodically (not always!) duplicated.
After placing an order, the user gets to the thank you page, on which a dataLayer object is created with the following content:

dataLayer

[
  {
    "gtm.start": 1594989221556,
    "event": "gtm.js",
    "gtm.uniqueEventId": 0
  },
  {
    "ecommerce": {
      "currencyCode": "RUB",
      "purchase": {
        "actionField": {
          "id": "135147",
          "revenue": "54990",
          "shipping": "",
          "coupon": "",
          "action": "purchase"
        },
        "products": [
          {
            "id": "182434",
            "name": "Смартфон Samsung Galaxy S20 128Gb Серый",
            "price": "54990",
            "category": "Мобильные устройства / Смартфоны / Galaxy S20",
            "position": "0",
            "quantity": "1"
          }
        ]
      }
    },
    "event": "gtm-ee-event",
    "gtm-ee-event-category": "Enhanced Ecommerce",
    "gtm-ee-event-action": "Purchase",
    "gtm-ee-event-non-interaction": "False",
    "gtm.uniqueEventId": 2
  },
  {
    "event": "gtm.dom",
    "gtm.uniqueEventId": 3
  },
  {
    "event": "gtm.load",
    "gtm.uniqueEventId": 7
  },
  {
    "event": "gtm.click",
    "gtm.element": {
      "metrikaId_0.44899286633488145": 12
    },
    "gtm.elementClasses": "b-cart_main_section_header",
    "gtm.elementId": "",
    "gtm.elementTarget": "",
    "gtm.elementUrl": "",
    "gtm.uniqueEventId": 8
  },
  {
    "event": "gtm.click",
    "gtm.element": {
      "metrikaId_0.44899286633488145": 25
    },
    "gtm.elementClasses": "b-cart_main_section_box_inner",
    "gtm.elementId": "",
    "gtm.elementTarget": "",
    "gtm.elementUrl": "",
    "gtm.uniqueEventId": 9
  },
  {
    "event": "gtm.timer",
    "gtm.timerId": 34,
    "gtm.timerEventNumber": 1,
    "gtm.timerInterval": 15000,
    "gtm.timerLimit": 1,
    "gtm.timerStartTime": 1594989221961,
    "gtm.timerCurrentTime": 1594989236963,
    "gtm.timerElapsedTime": 15002,
    "gtm.triggers": "7065235_106",
    "gtm.uniqueEventId": 10
  }
]

There are no duplicates in it. Through the Network in the developer panel of the browser, you can see that the request for analytics is sent only once.

What else could be the problem?

Answer 1

Through the Network in the developer panel of the browser, you can see that the request for analytics is sent only once.

check here 100500 times
and the backend may be smart enough to send more