# Add mutiple contacts to a segment - 400 Bad Request

**URL:** <https://forum.mautic.org/t/add-mutiple-contacts-to-a-segment-400-bad-request/38321>\
**Category:** Product Support\
**Tags:** segments, api\
**Created:** [June 30, 2026, 1:59pm UTC](https://forum.mautic.org/t/add-mutiple-contacts-to-a-segment-400-bad-request/38321 "2026-06-30T13:59:11Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![ailepet](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/ailepet/32/13324_2.png) [@ailepet](https://forum.mautic.org/u/ailepet)\
**Post date:** [June 30, 2026, 1:59pm UTC](https://forum.mautic.org/t/add-mutiple-contacts-to-a-segment-400-bad-request/38321/1 "2026-06-30T13:59:11Z")

</div>

**Your software**  
My Mautic version is: 7.0.0  
My PHP version is: 8.3.30  
My Database type and version is: MySQL 8.4.8

**Your problem**

Trying to perform a API request for adding a batch of contacts to a given segment (through n8n) always returns an HTTP 400 Bad Request error. I’m not sure how my syntax is incorrect here, I’ve tried to follow [the documentation](https://devdocs.mautic.org/en/7.0/rest_api/segments.html#add-contacts-to-segment) as close as possible.

```auto
{
  "errorMessage": "Bad request - please check your parameters [item 0]",
  "errorDescription": "This is a bad request.",
  "errorDetails": {
    "rawErrorMessage": [
      "400 - \"{\\\"errors\\\":[{\\\"code\\\":400,\\\"message\\\":\\\"This is a bad request.\\\",\\\"details\\\":[]}]}\""
    ],
    "httpCode": "400"
  },
  "n8nDetails": {
    "nodeName": "Segmente les contacts dans Mautic",
    "nodeType": "n8n-nodes-base.httpRequest",
    "nodeVersion": 4.4,
    "itemIndex": 0,
    "time": "30/06/2026 15:57:39",
    "n8nVersion": "2.21.1 (Self Hosted)",
    "binaryDataMode": "database",
    "stackTrace": [
      "NodeApiError: Bad request - please check your parameters",
      " at ExecuteContext.requestWithAuthentication (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+exporter-trace-otlp_2c2e1f47b69b34bef6f634a13cbf61d9/node_modules/n8n-core/src/execution-engine/node-execution-context/utils/request-helper-functions.ts:1368:10)",
      " at processTicksAndRejections (node:internal/process/task_queues:104:5)",
      " at ExecuteContext.requestWithAuthentication (/usr/local/lib/node_modules/n8n/node_modules/.pnpm/n8n-core@file+packages+core_@opentelemetry+api@1.9.0_@opentelemetry+exporter-trace-otlp_2c2e1f47b69b34bef6f634a13cbf61d9/node_modules/n8n-core/src/execution-engine/node-execution-context/utils/request-helper-functions.ts:1711:11)"
    ]
  }
}

```

 ![image](https://us1.discourse-cdn.com/flex020/uploads/mautic/original/2X/a/a74e04d119461cf2adf21280bf854b512df3b6c5.png)

I’ve tried to pass the query parameters outside the request body, but I get the same error.