Hello @j.jpg,

Thank you for sharing this post with the Community.

The 'Don’t show to existing Klaviyo profiles' option uses cookies (which will be collected when the user fills the form) to identify existing profiles. In effect, this means any user who previously filled out a Klaviyo form or clicked through a Klaviyo email will not see the form if this option is enabled.

With that said, if your goal is to target everyone who has not yet purchased, the easiest solution is to simply add a flow filter on your welcome flow. The flow filter will be defined as: What somebody has done > Placed Order > Zero Times over all time. This will exclude everyone from the Welcome flow who has previously purchased.

I hope that helps!