My custom checkout (Checkout SDK) is broken, can you debug it?

Yes. A custom build on the BigCommerce Checkout SDK or a misconfigured Optimized One-Page Checkout can throw on load, skip the shipping or payment step, or fail to take payment. We debug the SDK flow end to end, the checkout service calls, the step rendering, and the payment provider integration, reproduce it on a sandbox, fix the failing call, and verify a real test order completes before going live.