# Invalid value for custom field type

**URL:** <https://community.developer.atlassian.com/t/invalid-value-for-custom-field-type/37325>\
**Category:** Trello\
**Tags:** custom-field\
**Created:** [April 14, 2020, 12:25am UTC](https://community.developer.atlassian.com/t/invalid-value-for-custom-field-type/37325 "2020-04-14T00:25:45Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![PatricioChristianGar](https://avatars.discourse-cdn.com/v4/letter/p/85e7bf/32.png) [@PatricioChristianGar](https://community.developer.atlassian.com/u/PatricioChristianGar)\
**Post date:** [April 14, 2020, 12:25am UTC](https://community.developer.atlassian.com/t/invalid-value-for-custom-field-type/37325/1 "2020-04-14T00:25:45Z")

</div>

Hi,

I am working wtih Python and when I tried to update a custom field I have this error

> Invalid value for custom field type  
> Update Custom Field item on Card

PUT /1/cards/{idCard}/customField/{idCustomField}/item

Documentation example

```auto
{
 "value": {
 "text": "<string>",
 "checked": true,
 "date": "2018-03-13T16:00:00.000Z",
 "number": 2154
 }
}

```

I need to set number field but I do not know how pass this parameter in the querystring variable.

querystring = {‘number’: ‘123’,“key”:KEY,“token”:TOKEN}

response = requests.request(“PUT”, url, params=querystring)

Thanks a lot for you help, I appreciate so much.

---

<div class="post-metadata">

**Author:** ![nmansilla](https://sea1.discourse-cdn.com/atlassiandeveloper/user_avatar/community.developer.atlassian.com/nmansilla/32/33772_2.png) [@nmansilla](https://community.developer.atlassian.com/u/nmansilla)\
**Post date:** [April 14, 2020, 3:00am UTC](https://community.developer.atlassian.com/t/invalid-value-for-custom-field-type/37325/2 "2020-04-14T03:00:41Z")

</div>

Hi @PatricioChristianGar - welcome to the community. Here’s a link to a guide on custom fields in Trello. Scroll down to the section titled **Setting & Updating CustomFieldItems**.

[https://developer.atlassian.com/cloud/trello/guides/rest-api/getting-started-with-custom-fields/](https://developer.atlassian.com/cloud/trello/guides/rest-api/getting-started-with-custom-fields/)