Onboarding or manual enter of Ids not working

Hello,

I got a big problem and reading an trying to solve it since weeks!
If I activate Amazon Pay (AP) (even in Sandbox) I got an White screen in german:

Es gab einen kritischen Fehler auf deiner Website

Looks a bit like an WP Error and not Woocommerce or AP

If I try to login to AP and start the onboarding again, I get an Error on that Site “Systemerror”

The woo Log files shows this:

2022-02-03T09:40:50+00:00 CRITICAL Uncaught Exception: Unable to load file:  in /home/wp/disk/wordpress/wp-content/plugins/woocommerce-gateway-amazon-payments-advanced/vendor/amzn/amazon-pay-api-sdk-php/Amazon/Pay/API/Client.php:412
Stack trace:
#0 /home/wp/disk/wordpress/wp-content/plugins/woocommerce-gateway-amazon-payments-advanced/vendor/amzn/amazon-pay-api-sdk-php/Amazon/Pay/API/Client.php(379): Amazon\Pay\API\Client->setupRSA()
#1 /home/wp/disk/wordpress/wp-content/plugins/woocommerce-gateway-amazon-payments-advanced/includes/class-wc-amazon-payments-advanced-api.php(403): Amazon\Pay\API\Client->generateButtonSignature()
#2 /home/wp/disk/wordpress/wp-content/plugins/woocommerce-gateway-amazon-payments-advanced/includes/class-wc-gateway-amazon-payments-advanced.php(169): WC_Amazon_Payments_Advanced_API::get_create_checkout_session_config()
#3 /home/wp/disk/wordpress/wp-includes/class-wp-hook.php(303): WC_Gateway_Amazon_Payments_Advanced->scripts()
#4 /home/wp/disk/wordpress/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters()
#5 / in /home/wp/disk/wordpress/wp-content/plugins/woocommerce-gateway-amazon-payments-advanced/vendor/amzn/amazon-pay-api-sdk-php/Amazon/Pay/API/Client.php on line 412

I read a lot of Threads, tutorials an of cause your “Setting up Amazon Pay plugin V2”.

on another Site I could install the plugin an do the onboarding without any problems.

I don?t know any further and need your help, peeeease ??

christian

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