manav009

Hi @takayukister , Thanks for the quick reply.

Theme

• Active theme: Extice Child (v1.1.1)
• Parent theme: Extice by Opalthemes

Plugins directly related to Contact Form 7 / email Plugin Version (approx.) Contact Form 7 6.1.5 ReCaptcha v2 for Contact Form 7 (adds [recaptcha] tag back) Flamingo (stores CF7 submissions) WP Mail SMTP 4.7.1 — mailer: Google / Gmail API CF7 to Webhook (cf7-to-zapier) hooks wpcf7_mail_sent

Other active plugins on the site Plugin Version (approx.) Elementor 3.35.8 Header Footer Elementor 2.8.3 WooCommerce 10.5.3 Advanced Custom Fields (ACF) — Yoast SEO — Mailchimp for WordPress (MC4WP) 4.11.1 Wordfence 8.1.4 10Web Booster (tenweb-speed-optimizer) 2.32.11 — Delay all JS enabled Safe SVG — What The File 1.6.1 Clear Cache for Widgets 2.4.2 WP File Manager — UpdraftPlus — Duplicator — Migrate Guru —

Notes that may be relevant

1. We previously used CF7’s built-in reCAPTCHA v3 integration, but switched to ReCaptcha v2 for Contact Form 7 because the v3 script was not loading reliably (likely blocked by ad blockers / 10Web JS delay). reCAPTCHA v2 is now working — submissions pass validation (invalid_fields is empty).
2. 10Web Booster has “Delay all JS” on. Contact Form 7 and Google reCAPTCHA are excluded from delay.
3. Mail is sent via WP Mail SMTP → Google / Gmail API (email@company.com). The WP Mail SMTP test email succeeds, but form submissions sometimes return mail_failed. WP Mail SMTP Debug Events show many historical Gmail API 401 errors (May 26) and some successful sends today (June 1).
4. CF7 to Webhook appears in debug logs calling trigger_error_notification on wpcf7_mail_sent.
5. Custom child-theme code includes a wpcf7_before_send_mail hook that generates an inquiry ID (generate_inquiry_id) — no mail abort/skip logic.

Happy to test with plugins deactivated one by one if that helps narrow it down. Let me know what you’d like us to try first.

Thanks again.