Troubling linking to my paypal account

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.