Site email settings throw error when rsvp

I’m working on setting up the site to use smtp for better email deliverability. This is not related to your plugin. However, it’s affecting it negatively. I’m posting this just in case it’s helpful, and don’t currently need support.

If the email settings aren’t correct for the wordpress install (I’ve tried multiple SMTP plugins and also hand coding wp-config and functions.php), then when the end user RSVPs, the rsvp is successfully recorded, but the site shows the end user an error page.

It’s clearly a misconfiguration issue on my end, but wanted to add this info just in case it helps.