Troubleshooting

Most form problems show up on the submission itself, because FormThunder records each delivery's status, attempts and last error. Start in the dashboard, or ask your AI to run get_submission or test_form. If there's no submission at all, the request never arrived, so check the page with check_form_on_site. These are the common causes and fixes.

No email arrived

1. Check the submission's email delivery. Delivered means your mail provider accepted it, so look in your spam folder.
2. Skipped usually means no recipient on the form is verified. Click the verification link we sent, or add an address with add_linked_email.
3. Pending means it's still retrying. Failed shows the last error, and you can resend it.
4. If the submission is in the spam folder, restore it, and check why it was flagged. A honeypot field that's visible and gets ticked will flag a real person.
5. If its status is held, the account is over its monthly limit. See below.

400: Missing or invalid access_key

The form has no access_key field, or the value isn't a form's ID. Check for typos and that the field's name is exactly access_key.

400: Captcha failed

The form has a captcha set, and the post had no valid token. Add the widget and /client/script.js to the page, or set captcha to none on the form. For Turnstile, check that the widget's hostname list includes your domain.

403: This form doesn't accept submissions from this website

The origin isn't on the form's allowed_domains. Add it. Preview deployments and localhost are separate hosts, and server-side posts have no origin at all.

403: This form isn't accepting submissions

The form is paused. Resume it in the dashboard.

413: Too large

Requests stop at 6 MB, and direct files at 5 MB. Use the advanced uploader for files up to 25 MB.

429: Too many requests

Over 30 requests a minute from one IP address to one form. If your own server is posting for all your visitors, that's the likely cause. Post from the browser, or use POST /api/v1/submissions with an API key.

My files didn't arrive

Attachments need Pro, and attachments_enabled set on the form. Check the form has enctype="multipart/form-data". The JSON response's warnings tell you if files were ignored.

The autoresponder didn't send

The delivery shows as skipped, with a reason. It needs allowed_domains set, a post from one of them, and a field named email. Each address gets at most 3 a day. See the autoresponder.

A webhook keeps failing

Read the last error on the delivery. Your endpoint must be public HTTPS and reply with a 2xx within 30 seconds. After a fix, press resend, or run resend_deliveries. If the signature doesn't match, you're probably hashing parsed JSON rather than the raw body. See webhooks.

My submissions show as held

The account passed its monthly limit. Nothing is lost: they're stored and released when the account upgrades.

My AI says it can't verify an email

It can't. Verification needs someone to click a link in the inbox. Click it, then ask the agent to carry on.

Still stuck?

Email support@formthunder.com with the submission ID, or the form ID and the page URL.