First, you should know that WooRewards sends emails with the standard WordPress/WooCommerce method. It hasn’t its own method for sending emails. It also means that if some WooRewards aren’t sent, the same problem is likely to happen with WooCommerce emails.
Default Behavior of WordPress/WooCommerce
When you setup your WordPress website, you define a standard email address for the website and WordPress will try to send emails with that address. In addition, when you install WooCommerce, you can set up a second email address. This new address is used to send WooCommerce emails. WooRewards uses that address.
When your website tries to send an email, it sends an email request to your server. Most of the time, your server hasn’t the authorization to send emails with the address you’ve set in your WordPress/WooCommerce settings. Instead, it will use its own email parameters, sending your email with its own address. But it will also want to appear as if the mail was sent from your set address. This difference will often be blocked by the receiving mailbox.
How to ensure that your emails are received ?
The best way to ensure that your emails are being received is by using WP Mail SMTP. It will allow you to bypass the default behavior of WordPress and your hosting provider. Instead, you will be able to authentify your sent emails with your email provider and send all your emails through that provider.
WP Mail SMTP is free and easy to set up. It’s definitely a must have on your WordPress/WooCommerce/WooRewards website.