No notifications nor confirmations | WordPress.org

I have searched the forum discussions and implemented many suggestions with no resolution.

I’ve read
Testing Forms Before Launching
Troubleshooting Form Notification Emails

My “from” email matches my domain name.
I set up Brevo as SMTP. When I test via Brevo, the email comes to my inbox.
I’ve deactivated all plugins and used a WP 20xx theme. (I’ve since reactivated because they weren’t the problem)
For the confirmation, I’ve tried all 3 options (message, show page, go to URL)

When I hit submit, I get the “sending” text but then literally nothing: no confirmation regardless of which option I use and no notification.

I’m not sure what else to do.

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