Find the missing step
A successful application call to wp_mail does not prove the recipient received the message. Trace the event from the form or password reset through the configured mail transport, provider acceptance and the recipient mailbox.
Use an approved test address and record the time, sending domain, recipient and provider message ID where available. Avoid logging message bodies, passwords, reset links or SMTP credentials. Check spam or quarantine as well as the inbox.
Check the application and transport
Confirm the expected WordPress hook or plugin actually created a message and that the configured sending method is available to the host. If using SMTP or an email API, examine connection, TLS, authentication and provider responses in restricted logs. A wrong port or blocked outbound connection produces a different failure from a provider accepting a message and later rejecting delivery.
Review the From address and provider policy. An arbitrary From domain may be rejected or fail authentication if the sending service is not authorized. Check the sending domain's SPF, DKIM and DMARC configuration against the actual provider documentation; avoid adding multiple SPF records.
Test delivery without creating noise
Send one controlled test and follow its identifier in the provider's event history. Distinguish accepted, deferred, bounced and delivered-to-recipient-server states. Delivery to a recipient server does not guarantee placement in the inbox.
After a focused fix, test a representative password reset or contact form, verify credentials remain private, and monitor a small number of subsequent events. Rate-limit repeated testing so the investigation does not resemble unwanted mail.
Further reading
Read the official documentation. For help applying these checks, explore Clouvenix services.