BP-3646 Age verification using iDeal and iDIN throws null error (3.13.1)

My client installed the Buckaroo plugin 3.13.1 on his website and updated Woocommerce to 9.0.2. He wishes to use iDIN to verify the age of a customer through iDEAL.

For the eye: this setup seems to work as the iDIN logo is presented and the integration works with the customers keys and secrets.

Unfortunately, during checkout a 500 is thrown for a call to: ?wc-api=WC_Gateway_Buckaroo_idin-identify&issuer=BANKNL2Y

The following stacktrace is fished out of the console:

{
    "code": "internal_server_error",
    "message": "<p>Er heeft zich een kritieke fout voorgedaan op deze site.<\/p><p><a href=\"https:\/\/wordpress.org\/documentation\/article\/faq-troubleshooting\/\">Meer informatie over probleemoplossing in WordPress.<\/a><\/p>",
    "data": {
        "status": 500,
        "error": {
            "type": 1,
            "message": "Uncaught Error: Call to a member function get_failed_url() on null in \/home\/cabrio\/public_html\/wp-content\/plugins\/WooCommerce-3.13.1\/library\/common.php:537
Stack trace:
\/home\/cabrio\/public_html\/wp-content\/plugins\/WooCommerce-3.13.1\/controllers\/IdinController.php(74): fn_buckaroo_process_response(NULL, Object(BuckarooResponseDefault))\n#1 \/home\/cabrio\/public_html\/wp-includes\/class-wp-hook.php(324): 
IdinController->identify('')\n#2 \/home\/cabrio\/public_html\/wp-includes\/class-wp-hook.php(348): 
WP_Hook->apply_filters('', Array)\n#3 \/home\/cabrio\/public_html\/wp-includes\/plugin.php(517): 
WP_Hook->do_action(Array)\n#4 \/home\/cabrio\/public_html\/wp-content\/plugins\/woocommerce-legacy-rest-api\/includes\/class-wc-api.php(150): 
do_action('woocommerce_api...')\n#5 \/home\/cabrio\/public_html\/wp-includes\/class-wp-hook.php(324): 
WC_API->handle_api_requests(Object(WP))\n#6 \/home\/cabrio\/public_html\/wp-includes\/class-wp-hook.php(348): 
WP_Hook->apply_filters(NULL, Array)\n#7 \/home\/cabrio\/public_html\/wp-includes\/plugin.php(565): 
WP_Hook->do_action(Array)\n#8 \/home\/cabrio\/public_html\/wp-includes\/class-wp.php(418): do_action_ref_array('parse_request', Array)\n#9 \/home\/cabrio\/public_html\/wp-includes\/class-wp.php(813): 
WP->parse_request('')\n#10 \/home\/cabrio\/public_html\/wp-includes\/functions.php(1336): WP->main('')\n#11 \/home\/cabrio\/public_html\/wp-blog-header.php(16): wp()\n#12 \/home\/cabrio\/public_html\/index.php(17): require('\/home\/cabrio\/pu...')\n#13 {main}\n  thrown",
            "file": "\/home\/cabrio\/public_html\/wp-content\/plugins\/WooCommerce-3.13.1\/library\/common.php",
            "line": 537
        }
    },
    "additional_errors": []
}

I did some debugging and noticed that the function fn_buckaroo_process_response($1 = null, $2) has a variable that defaults to null, so the call to that method (which I could not directly find yet) seems to be incorrect.

Seeing the call is using /?wc-api instead of the new wp-json I also installed the Woocommerce Legacy API as additional plugin to re-enable this. But enabling or disabling this plugin (and thus enabling or disabling WC-API) seems not influence the outcome.

buckaroo-it / WooCommerce

BP-3646 Age verification using iDeal and iDIN throws null error (3.13.1) #273