> For the complete documentation index, see [llms.txt](https://docs.windsor.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.windsor.io/integrations/klaviyo/prevent-duplicate-emails.md).

# Prevent duplicate emails

To prevent sending duplicate video emails to the same person, you can use Klaviyo's built-in "Flow filters". We highly recommend using these in your flows.\
You can set them up like this:

1: Select the flow you'd like to edit.

![](https://637946555-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FOHwTvdR0UFDXjRFF5A5E%2Fuploads%2F4VGaCs6RIVkpzMYVxDJ2%2FFlows%20%7C%20Klaviyo%202022-09-21%2010-41-52.png?alt=media\&token=8739e799-7562-47ea-b24a-4d986e679e5e)

2: Click the "**Trigger**" box and select "**Flow filters**".

![](https://637946555-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FOHwTvdR0UFDXjRFF5A5E%2Fuploads%2F5PUnSOcOA8D2CHrTDVrY%2FCustomer%20Thank%20You%20-%20New%20vs.%20Returning%20%7C%20Flows%20%7C%20Klaviyo%202022-09-21%2010-43-27.png?alt=media\&token=fc4878e1-936a-47c9-9919-a62f51f6ebef)

3: Click the "**Add a flow filter**" button.

![](https://637946555-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FOHwTvdR0UFDXjRFF5A5E%2Fuploads%2Ft22xUKRbaP2SykNUhVuz%2FStep%203.png?alt=media\&token=3be690f4-0e5e-4a96-a4b7-09be732a3008)

4: Select "**Has not been in this flow**" from the first dropdown and leave the "at any time" box as-is.\
Click "**Save**" after that.

![](https://637946555-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FOHwTvdR0UFDXjRFF5A5E%2Fuploads%2FB1DuQAZJD9ttxzJApJdS%2FStep%204.png?alt=media\&token=ef192fd5-c133-48ce-99b6-b5732c1b70a6)

That's it! These steps will prevent people from being added to this flow a second time.