I tested your website and found the source of the issue. The error URL has EWP_SETTINGS in it, which means you have an encryption setting turned on in your PayPal account which is blocking payment acceptance from your shopping cart, since the Shopping Cart is not using the Encryption Settings.
If you previously blocked payments from unencrypted buttons, here’s how to accept all payments:
Log in to your PayPal account.
Click the Business Profile icon beside "Log Out" and select Profile and settings.
Click My Selling tools.
Click Update near 'Website preferences.'
Select ‘Off’ next to ‘Block Non-encrypted Website Payment.’
Click Save.
Once you turn off the Encrypted Websites Setting in your PayPal Account, you will be able to accept payments.
Thank you,
Jennifer
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