Hi again
I've been using your plugin successfully for a few months now, accepting payments via Paypal and all has been working very well on my site: http://www.surreygreenlanetours.co.uk/index.php/book-online-now/
I've just had an email from someone trying to make a booking saying they were getting a PayPal error when trying to make payment.
I've attempted the booking myself and I'm getting the error:
SetExpressCheckout API call failed.
Detailed Error Message: Security header is not valid
Short Error Message:
Error Severity Code: Error
I've deleted, renewed and replaced the API credentials but it still generates the same error.
Any ideas?!
Many thanks, Rob