Confirm the failure
Send a test using a different email address from your own. Check the inbox, the spam folder, and any junk or quarantine area in your mail system. Look in the form plugin's entry log, if it keeps one, to see whether the submission was recorded. If entries exist but emails do not, the problem is delivery, not the form.
Why website email fails
By default, many sites send notifications straight from the web server, using your domain in the From line. Receivers see a message claiming to be from your domain but sent by a server not listed in your authentication records, so it fails checks and lands in spam or is rejected. Some hosts also restrict or disable that kind of sending.
Fix one: send through a proper mail service
Connect the site to an SMTP service or a transactional email provider using a plugin or built-in setting. The mail then goes out through authenticated channels. Use a From address on your own domain that matches the service, and add the provider's SPF and DKIM records to your DNS.
Many mailbox providers allow app-specific passwords or API keys for this purpose, which is safer than using your main password.
Fix two: check the settings
Verify the To address is typed correctly and that your form's From address is a real mailbox on your domain, not the visitor's address. Setting the visitor's email as the From address often causes failures; place it in Reply-To instead. Check that a recent update did not reset the notification settings.
Look for conflicts with security or caching plugins that block the form request.
Fix three: look at the receiving side
Your own mailbox may be filtering. Create a rule that allows messages from your site's address. Check that the mailbox is not full. Review any forwarding set up from your domain to a free email account, since forwarded mail can fail authentication checks.
Search the logs your host provides, or install an email logging plugin, to see whether messages were sent, rejected or deferred.
Prevent a repeat
Set up a monthly test submission. Add a backup path, such as saving entries in the dashboard and displaying a phone number near the form. Document the setup: which service sends mail, which DNS records support it and who holds the login.
If you cannot find the cause after these steps, ask your host or web provider to review mail logs and DNS records with you.
A final tip is to separate who the email appears to come from and who should receive replies. Let the From line be a stable address on your domain, and put the visitor's address in Reply-To so that pressing reply goes straight to them. This one setting resolves a large share of missing-form-email cases without any server changes.
Common questions
Why does the form work for some inboxes only?
Providers differ in filtering. The same message may pass at one and fail at another.
Should I use my Gmail address as the sender?
Not from your website. Use an address on your own domain, with the mail service authorized in DNS.
Can I trust the thank-you message?
No. It only means the form accepted the data. Test delivery separately.
This guide is general information. Search engines change how they work and their guidelines; check Google's current documentation for your situation. Nobody can guarantee a ranking.