I can't get the Paypal Widget to work

When I click on the Submit button I get a warning from PayPal that there is a problem with the email supplied by the seller. The client says this is the correct email. Maybe I just don't have it entered properly. 

See the warning in the screen shot attached. 

Please help..... :)

You have not entered an email at all.

To change it correctly, you can either go to the wizard by clicking on the wand or delete the field and add it back again.