# When importing contacts using CSV file, Mautic merges half of them (Bug?)

**URL:** https://forum.mautic.org/t/when-importing-contacts-using-csv-file-mautic-merges-half-of-them-bug/27051
**Category:** Product Support
**Created:** [February 15, 2023, 7:37pm UTC](https://forum.mautic.org/t/when-importing-contacts-using-csv-file-mautic-merges-half-of-them-bug/27051 "2023-02-15T19:37:55Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![giuseppe0208](https://avatars.discourse-cdn.com/v4/letter/g/e9c0ed/32.png) [@giuseppe0208](https://forum.mautic.org/u/giuseppe0208)
#### Post date: [February 15, 2023, 7:37pm UTC](https://forum.mautic.org/t/when-importing-contacts-using-csv-file-mautic-merges-half-of-them-bug/27051/1 "2023-02-15T19:37:55Z")

</div>

Hi,

**Software:**  
My Mautic version is: 4.4.6  
My PHP version is: PHP Version 7.4.33  
My Database type and version is: MySQL - 5.7.41

**Problem:**  
I’m having issues when importing data from a CSV file into the contacts segment. While I’m just importing a CSV with four columns and only one unique identifier (email), when importing the dataset Mautic won’t recognize the majority of the contacts. As you can see in the image below, only 833 contacts have been inserted and 735 updated. Also, when importing the file once again, 379 new contacts were inserted and 1189 updated but it still does not import the complete dataset.

How can I properly import the complete dataset without having these errors? Is it a matter of format?

 ![Captura de Pantalla 2023-02-15 a la(s) 13.08.07](https://us1.discourse-cdn.com/flex020/uploads/mautic/original/2X/d/dca3892e758423f93732ce1f58b6dc788a27fa1a.png)

This is an example of the data being imported:

 ![Captura de Pantalla 2023-02-15 a la(s) 17.39.44](https://us1.discourse-cdn.com/flex020/uploads/mautic/original/2X/0/044e48c6b3666a6a7616e3f52d764a0ef97b07a5.png)