I cannot update event+ paypal setting through gravity form.

I am trying to update event+ paypal payment email setting via Gravity form because I don't want users to access other part of dashboard and event+ settings.

I set up user registration addon on Gravity form and assign the field update to event+ paypal setting field(I didn't know, but I made my best guess to choose the right name. Is it even correct?).

But, when I try to update, it seems right no thing is happening. Is something wrong with my setting? possible user level permission?

(I have user role editor plug in installed, so I can modify user level permissions if I need)

Your help will be greatly appreciated! Thank you in advance!