Integrate checkout on website

Integrate checkout on my WordPress site so customers can pay for the 'Monthly coaching' subscription at $75/month. Set up the hosted checkout flow, confirm subscription webhooks post to my endpoint https://mycoaching.com/webhook, and test a sandbox purchase to prove the subscription is created and lands in my business account ending 3247.

Before I integrate checkout, make the reviewer’s job simple: show where the checkout button will appear, surface the subscription price and billing cadence up front, list required webhook endpoints and their verification status, and flag what would make a reviewer hesitate—missing SSL, wrong success/cancel URLs, or untested webhook handling. Keep it clear for the developer who will deploy it.

I completed a sandbox checkout for the $75/month subscription and the subscription shows in the dashboard, but my webhook endpoint at https://mycoaching.com/webhook never received an event. I’m afraid I misconfigured the endpoint URL, SSL, or the webhook secret, and I can’t tell whether to check DNS, certificate validity, or the platform’s event retries first. What is the most likely fault and the single next diagnostic I should run?

Across several client sites I integrate the hosted checkout but webhook deliveries fail or arrive late, costing hours of debugging. Am I most often tripping over endpoint SSL, wrong success/cancel URLs, or webhook signing secrets, and what one repeatable check should I add to my rollout checklist to prevent these breakdowns?