Hi,<\/p>\n
I have a clean WordPress WooCommerce environment where i’m testing an issue I have. I have the following WooCommerce settings:
\n– Enabled taxes
\n– Currency options > Number of decimals: 0<\/p>\n
Now I have products like 349,95 which is rounded up and shown as 350 because i’ve disabled the decimals. This is all working great until I start the Mollie payment. So I’ve checked the debug logs and this is what I get:<\/p>\n
2025-08-04T15:23:39+00:00 Foutopsporing [2025-08-04T15:23:39+0000] Error executing API call (422: Unprocessable Entity): Line item 1 is invalid. The ‘vatAmount’ field is off. Expected to be \u20ac95.38 (\u20ac549.55 \u00d7 (21.00 \/ 121.00)), got \u20ac95.00. Documentation: https:\/\/docs.mollie.com\/reference\/handling-errors. Request body: {“status”:422,”title”:”Unprocessable Entity”,”detail”:”Line item 1 is invalid. The ‘vatAmount’ field is off. Expected to be \u20ac95.38 (\u20ac549.55 \u00d7 (21.00 \/ 121.00)), got \u20ac95.00″,”field”:”lines.1.vatAmount”,”_links”:{“documentation”:{“href”:”https:\/\/docs.mollie.com\/reference\/handling-errors”,”type”:”text\/html”}}}. Field: lines.1.vatAmount<\/p>\n
2025-08-04T15:23:39+00:00 Foutopsporing ideal: Failed to create Mollie payment object for order 8123: [2025-08-04T15:23:39+0000] Error executing API call (422: Unprocessable Entity): Line item 1 is invalid. The ‘vatAmount’ field is off. Expected to be \u20ac95.38 (\u20ac549.55 \u00d7 (21.00 \/ 121.00)), got \u20ac95.00. Documentation: https:\/\/docs.mollie.com\/reference\/handling-errors. Request body: {“status”:422,”title”:”Unprocessable Entity”,”detail”:”Line item 1 is invalid. The ‘vatAmount’ field is off. Expected to be \u20ac95.38 (\u20ac549.55 \u00d7 (21.00 \/ 121.00)), got \u20ac95.00″,”field”:”lines.1.vatAmount”,”_links”:{“documentation”:{“href”:”https:\/\/docs.mollie.com\/reference\/handling-errors”,”type”:”text\/html”}}}. Field: lines.1.vatAmount<\/p>\n
As you can see the amount sent to Mollie doesn’t correspond with the amount which Mollie calculates. This is the POST data:<\/p>\n
{\n "amount": {\n "currency": "EUR",\n "value": "550.00"\n },\n "description": "Bestelling XXXX",\n "redirectUrl": "https:\/\/xxxxx\/afrekenen\/order-received\/XXXX\/?key=wc_order_XXXX&order_id=XXXX&filter_flag=onMollieReturn",\n "webhookUrl": "https:\/\/xxxxx\/wc-api\/mollie_wc_gateway_ideal?order_id=XXXX&key=wc_order_XXXX&filter_flag",\n "method": "ideal",\n "issuer": "",\n "locale": "nl_NL",\n "dueDate": "",\n "metadata": {\n "order_id": XXXX\n }\n}<\/code><\/pre>\n","protected":false},"template":"","class_list":["post-18584824","topic","type-topic","status-publish","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/wordpress.org\/support\/wp-json\/wp\/v2\/topic\/18584824","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wordpress.org\/support\/wp-json\/wp\/v2\/topic"}],"about":[{"href":"https:\/\/wordpress.org\/support\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/wordpress.org\/support\/wp-json\/wp\/v2\/topic\/18584824\/revisions"}],"wp:attachment":[{"href":"https:\/\/wordpress.org\/support\/wp-json\/wp\/v2\/media?parent=18584824"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}