Problem with PayPal gateway checkout
I am using Vantage 4.2 having upgraded from a much older version which had some customisations
Most things are working fine but I am having a problem with PayPal checkout.
Pricing table part is fine, Add listing form is fine and I get to select gateway page. Payapl is the only payment method I have set up.
Screenshot 2020-07-13 at 23.47.18.jpg
The problem is, when I click the "Proceed to checkout" button, I get this page and can continue no further:
Screenshot 2020-07-13 at 23.47.05.jpg
Please can you advise or tell me where I should be looking to fix this?