What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
I've checked your form and I can see it redirects to PayPal without any problem when selecting some products:
Do note that the form will redirect to PayPal as long as a product is selected on the payment section, otherwise the form will only show the thank you page.
If you need to always redirect your users to PayPal payment page then you need to set the payment field as required, this way your users will need to select at least one product to submit the form.
Hope this helps.