My payment method isn't showing up on Form?

Hello! I am trying to add a payment option for my form and I keep getting a warning saying there is one already set up.  I've gone through the form multiple times and tried to fill it out but I cannot find this anywhere.  I've attached a screenshot with the warning.  Can you please instruct me further to where I should be able to see this option? 

Thanks! 

Hello,

I have checked your form. You have already have a payment option "Purchase Order". The purpose of this option is to get orders without any payment integration. In order to accept payments through a vendor like paypal, you have to remove the "Purchase Order" and add the vendor as you like. And then configure your products just like you did for "Purchase Order". Please note that there can be only one payment tool on a form.

Hope this helps

Best Regards