Checkout Not Working: How to Trace the Failing Payment Step

The symptom

Customers report they can't complete a purchase, or you notice orders drying up while traffic stays normal. It shows up in a few shapes: the pay button spins forever or does nothing, card details are rejected with a vague message, the page errors out after "Place order", or — the most costly variant — the customer is charged but no order lands in your admin and no confirmation email goes out. Each shape points at a different layer, so the first job is to reproduce it and note exactly where the flow dies.

What it usually means

A silent, non-submitting button is usually a front-end break — a JavaScript error, a failed asset, or a plugin/theme conflict stopping the checkout script. A clear decline or gateway error ("Your card was declined", "Invalid API Key") points at the payment provider: wrong or test-vs-live keys, an expired credential, or a currency/country the account can't process. Payment taken but no order created almost always means the webhook from the gateway back to your site is failing — unreachable URL, wrong signing secret, or a 500 error while the order is being written. These three buckets cover the large majority of checkout failures.

What we check first

We reproduce a real transaction and follow it layer by layer. First the browser console and Network tab during checkout (F12) — a red 500 on the AJAX/submit request, or a blocked script, names a front-end or server break immediately. Next the gateway's own logs: in Stripe, Developers > Events shows whether a PaymentIntent was even created and its status (succeeded, requires_payment_method, canceled); Developers > Webhooks shows delivery attempts with the exact HTTP response your site returned — a wall of 500 or 404 with "signature verification failed" is the smoking gun. On the store side we open the platform log: WooCommerce > Status > Logs (files under wp-content/uploads/wc-logs/), plus the server's PHP error log for fatal errors during order creation. We confirm keys are live-mode and match the webhook signing secret (whsec_...), and that the webhook endpoint URL returns 200 to a test event, not a redirect or a login wall.

What you can safely check yourself

Place one small real test order and watch what happens — this alone tells you which of the three buckets you're in. Open the browser console (F12 > Console) during checkout and note any red errors. Log into your payment provider dashboard and check whether the charge/PaymentIntent actually appears and its status; if the money was taken, look for the matching order in your admin. In Stripe, open Developers > Webhooks and see whether recent deliveries show green (200) or red — a red endpoint with retries is a strong, self-evident signal you can hand straight to whoever fixes it.

What NOT to touch

Don't rotate, regenerate or delete API keys or the webhook signing secret while diagnosing — you can turn a recoverable issue into a fully dead integration, and any in-flight payments lose their link to orders. Don't switch the store or gateway between test and live mode on production to "see if it helps". Don't bulk-update, deactivate or reinstall payment plugins on the live site, and don't edit checkout template or functions files directly. If customers have been charged without orders, do not issue blind refunds before the payments are reconciled — capture the list of affected charges first.

What a 30-minute diagnosis can determine

In a focused 30-minute session we can normally pin the failing layer and name the concrete cause: a specific JavaScript/plugin conflict, a mismatched or test-mode key, a gateway rejecting a currency or country, or a webhook failing with a signature or 500 error. We can tell you whether payments are being taken (and how many orders are affected and recoverable), whether it's a configuration fix or a code-level bug, and what the safe next step is. Often the fix itself — correcting a webhook URL, aligning the signing secret, or resolving a plugin conflict — fits inside that window or the one just after.

When it becomes a bigger job

It grows beyond a quick fix when the checkout has been customised at code level (bespoke payment flow, custom order-creation logic) that now throws fatal errors, when a recent platform or plugin update changed the gateway integration, or when many customers were charged without orders and the payments must be reconciled and orders rebuilt or refunded cleanly. Multi-gateway setups (Stripe plus PayPal plus an ecommerce plugin) and subscription or split-payment logic also take longer, because each path has to be traced and tested independently before any change ships.

Frequently asked questions