Create SendGrid Webhook Event Listener
SendGrid can send events to your WordPress site which will inform Groundhogg if an email bounced or was marked as spam so that Groundhogg will no longer send emails to problematic contacts.
The default API permissions are not sufficient to register the webhook, so you need to update the API KEY permissions to allow Groundhogg to register it for you.
Go to your SendGrid API Key Settings and edit the API key you created for your WordPress site.
Under Mail Settings change the Event Notification access to Full Access.
Then save your changes!
In WordPress go to Groundhogg > Settings > Email > SendGrid and click the Test API Connection to automatically configure the webhook endpoint.
You can verify that it worked by going to your SendGrid Mail Settings and check if the Event Webhook is enabled.