Problem with Paypal Payment Gateway on cart page

Hello, I’m having a problem when using your multi currency plugin. When I pressed ‘Pay with PayPal’ button on my cart page with changed currency, the pop-up window appeared then went away after 1 – 2 seconds, and I got this error message: “PayPal error (10605): An error (10605) occurred while processing your PayPal payment. Please contact the store owner for assistance.” (attached image). However, the PayPal button worked fine when I changed the currency to US Dollar, and I already turned off the ‘Enable Cart Page’ option. Can you fix this for me? Thank you.