embed form is getting gray out after being submitted

 Hello, I've created a form which uses paypal invoice. However when the customer submits the form a grey error page appears. However the invoice is still generated and sent to both me and the customer.

My issue is that the grey page looks really unprofessional and I cannot get rid of it. Any chance you can let me know how??

Can you please try embedding your form using the iFrame code?

Guide:https://www.jotform.com/help/148-Getting-the-Form-iFrame-Code

Please give it a try and let us know if the issue still remains.