PayPal payments just gives the customer an error, does not accept payments

I have checked your form and I can see it redirects to PayPal without any problem: 

However, your payment field is not required which means that the form can be submitted without even selecting an product, you should set it up as required if you need to always redirect your users to the payment page: 

If you're still unable to complete a payment could you please share us a screenshot of the message or error you're receiving? 

This guide will help you to add the screenshot with your next reply: How-to-add-screenshots-images-to-questions-in-support-forum

We will wait for your response.