What might cause this error?

Hi @alexliii,

Nonce validation is a security feature that occurs in many different parts of the plugin. Sometimes, this can be related to caching, but normally, it should not cause problems with payment itself.

You might try to apply this filter to disable the cart simulation:

add_filter( 'woocommerce_paypal_payments_simulate_cart_enabled', '__return_false' );

However, I’m not certain this will resolve the problem.

It would be helpful if you could reproduce this issue using a sandbox account and a test credit card, ideally in a staging environment. Then, you can run a conflict test to determine if a third-party plugin conflict is causing the problem.

To do a conflict test, please start by disabling any caching plugins (I see Auotptimize on your site), then you may try with a default theme, and if the issue persists, you can try disabling all other plugins except WooCommerce and WooCommerce PayPal Payments.

Learn more about conflict tests here: https://woocommerce.com/document/how-to-test-for-conflicts/.

Please let us know your findings!

Finally, I since this request is related to WooCommerce PayPal Payments, kindly open a new thread here: https://projectdmc.org/support/plugin/woocommerce-paypal-payments/#new-topic-0 so we can follow this discussion in the proper channel! I’m marking this one as resolved and we can take it from there.



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