> For the complete documentation index, see [llms.txt](https://docs.sportradar.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.sportradar.com/uof/error-handling/error-catalogue/getting-null-trying-to-fetch-category-from-tournament-object.md).

# Getting NULL trying to fetch category from tournament object

**Error Description**

Customers are encountering a "Null Reference Exception" (as follows) when attempting to fetch categories from a tournament object that is successfully cached within the SDK.

```
Object reference not set to an instance of an object
```

**Applies to**

* UOF SDK .Net (v1.56.0) and
* UOF SDK .NetCore (v1.29.0) or older

**Symptoms**

When a user requests a tournament associated with a category and/or sport that hasn't been obtained and cached under the "All Sports" or "All Tournaments for All Sports" endpoints, category data will not be returned.

**Resolution**

Fix was published in versions UOF SDK .Net (v1.57.0) and UOF SDK .NetCore (v1.30.0). The user needs to upgrade to the aforementioned or later versions of the SDK.


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