I already have an order form connected with PayPal through Go Central

I already have an order form connected with PayPal through Go Centeral on my website with GoDaddy. Can I add this coupon to that?

Yes, you can add the coupon code to the form within the form builder. Is this the form you are referring to https://form.jotform.com/83486281403155? If so, log in to JotForm and access it on that link to make changes. The changes will reflect on the embedded form on your website with GoDaddy.

Refer to these guides:

How to Create Your First Web Form

PayPal forms

How to Add Coupon Code to Payment Forms

Do let us know if you require further assistance.

No, I am not using that for. I already have a payment from through GoDaddy Go Centeral, I just want to add the discount widgets to that form by cpoying the code. Can this be done. If so can you provide me with the code or tell me how to find it? Thank you.
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Unfortunately, it is not possible unless you will re-create the order form through our form builder. The coupon codes in our form builder is only for forms that are created through Jotform. It cannot be integrated with other payment forms outside Jotform builder. 

Okay so I have completed the form and the coupon widget and it is now on my website. The only problem I am having is that when I try to process it I get an error message stating " "client authentication not verifed" can you help with that?
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You are using Paypal Checkout integration in the form, and you are using invalid credentials. Please follow the steps here https://www.jotform.com/help/542-How-to-integrate-PayPal-Checkout-with-your-form. 

Also, note that you need to have a premier or a business PayPal account to use the Checkout integration.

Thank you, this worked perfectly, I appreciate all your help.
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