Autoresponder email not working after payment is made

I have a payment option on my form and when a purchase has been successfully made the customer views the thank you page and receives a receipt from Paypal. All good. However the autoresponse email doesn't now get sent since I added the payment widget. It is important that the email does get sent to the purchaser so have I done something wrong with the set up please?

Your settings are all good. The autoresponder is working as far as my test is concerned. Although I have bypassed the payment section, that's the same thing. But we will investigate this further. Would you mind sharing us the email addresses of the submitters that are not getting your autoresponder email? We'll check our log. 

Note that you can also check your email log for the autoresponders: https://www.jotform.com/help/293-How-to-view-all-your-form-Email-History. Clicking the log link will allow you to see if the email has failed or sent. 

I look forward to your reply.