How do I switch from purchase order to add PayPal?

I'm the Payments tab in the editor and I can't see to click off of "purchase order" to change it to be integrated with PayPal...  It says "only have one payment field per form." I don't want to have two, I just want to switch it, but it won't seem to change when I click...

You can only have 1 payment processor on a single form. You need to delete the existing payment field in order to add another one.

When you delete the existing payment field, the products should still be available when you add the Purchase Order tool. 

I cloned your form and I noticed that you are already using Purchase Order.

Let us know if you need further help. Thank you.

I apologize, I misread your inquiry.

When you delete the existing Purchase Order field, the products should still be available when you add the PayPal integration. 

In the Form Builder, click the Purchase Order field and then click the "Trash" icon. After that, add the PayPal integration and the products will appear. Just click the "Properties" icon in the payment settings so that you can enter your PayPal credentials.

Here's a screen capture of the cloned form:

Related guide: https://www.jotform.com/help/391-How-to-Integrate-Form-with-Paypal

Hope that helps. Thank you.