Your form says “Thanks!” — so where did the lead go?

A submission has two halves. Uptime tools watch one.

The POST succeeds and the page shows your success message — that part is almost always fine. The lead reaching its destination is the half that silently breaks. Because the success message is usually tied to a 200 response, your site keeps looking perfect while the CRM stays empty.

Five ways a "successful" form loses leads

Webflow form stopped sending emails?

If your Webflow form stopped sending notification emails, check the form's notification settings first: Webflow documents that clicking the unsubscribe link in any form notification email silently clears the “Send form submissions to” field, and an empty or mistyped recipient stops delivery entirely. Submissions usually keep arriving in your site's Forms data while the email leg is broken — so confirm storage first, then fix delivery. Three checks, no developer needed:

1. Re-check the recipient field. Open the form's notification settings and confirm the “Send form submissions to” addresses are present and typo-free. Webflow's documented silent killer: anyone clicking unsubscribe in a notification email wipes the field, and it stays blank until you re-add the address.
2. Split storage from delivery. Check whether submissions are still being stored in your site's Forms data. If they're there, only the email leg broke — look at spam filtering next (Webflow notes role-based addresses like info@ are filtered more often and recommends a name-based address). If they're missing too, look for a custom form action: with one set, submissions bypass Webflow entirely and no notification email is ever sent.
3. Check the plan's recipient limits. On the free Starter site plan, notification emails are capped at five recipients who must all be Workspace members — adding outside or additional recipients requires a paid site plan.

Source: Webflow Help Center — “Why am I not receiving form notification emails?”. The end-to-end canary check below works on Webflow exactly as on any other platform — it's how you find out the morning delivery breaks, instead of at the end of a quiet week.

Paste this into your incident notes

Lead form delivery triage

[ ] Search the destination (CRM/sheet) for the canary email address.
[ ] Open the Zap/Make/n8n run history; look for failed or paused runs.
[ ] Confirm the destination API token is still valid (not rotated/expired).
[ ] Submit a manual test from incognito; watch the network panel for the POST.
[ ] Check the spam quarantine if delivery is by email.
[ ] Confirm the CRM webhook URL still matches after any recent migration.
[ ] Re-run / replay any leads held while the path was broken.

Two checks — and the second is the one nobody runs

The first check proves the form accepts data. The second proves the data actually arrived downstream. Submit a canary lead on a domain you own and use nowhere else, then query the destination and assert the canary appears in a recent record. Set the destination cadence at least as long as its slowest batching window to avoid false alarms.