Recently we experienced an issue while making SandBox Payment on PayPal. We were using Express Checkout. The error we are getting is as follows

“We aren’t able to process your payment using your PayPal account at this time. Please go back to merchant and try using a different payment method.”

We tried making payment with different PayPal sandbox buyer account with registered country as USA. But it doesn’t work.

Finally we created new seller account and seleted US while registering. Used new API credentials and tried again.

It worked well. We still waiting for PayPal response on this issue.