When you navigate to Admin>Munchkin, you see option to select Workspace. Why is that?
If you don't use the special workspace Munchkin code, the people will be assigned to the default partition that was created when your account was set up. It's named "Default" initially, but you might have changed that in your own Marketo account.
You can only use one Munchkin tracking script for a single partition and workspace on a page. Do not include tracking scripts for multiple partitions/workspaces on your website. I would also like to mention that Landing pages created in Marketo automatically contain tracking code, so you don’t need to put this code on them.