“Failed security check”-issue

Hello Addify-Team,

We run into an “Failed security check”-Issue with the Quick-Buy-Now-Button.

It occurs when a new visitor clicks the “Anmelden”-button for “Aufbautraining”:
https://www.eft-center-hannover.de/produkt/eft-aufbautraining/

Once you ordered another training, you can order “Aufbautraining”
E.g. when you first click the “Anmelden”-button for “Basistraining”
https://www.eft-center-hannover.de/produkt/eft-basistraining/
then the “Anmelden”-button for “Aufbautraining” works perfectly
https://www.eft-center-hannover.de/produkt/eft-aufbautraining/

This is even true after removing both trainings from the cart and then click the “Anmelden”-button for “Aufbautraining” again:
https://www.eft-center-hannover.de/produkt/eft-aufbautraining/

After emptying the cart, closing the browser, opening the browser, the issue is there again. Which probably means that something necessary is missing in the session context.

FYI
– “Conditional Checkout Fields for WooCommerce” is also used for this product.
– This shop runs inside a WP-multisite. The test-site, which is a WP-single-site, doesn’t show this issue. See: https://www.tangodialog.de/produkt/eft-aufbautraining/
– WordPress and Plugins versions are all up-to-date.

Thanks for having a look into this!

Best wishes,
Hendrik

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