If you are experiencing issues where WooCommerce notifications contain empty placeholders (e.g., {{order_id}}, {{billing_first_name}} appearing blank), enabling High-Performance Order Storage (HPOS) may help resolve the issue.
Ensure you are running WooCommerce 7.1+, as HPOS is available in newer versions.
Steps to Enable HPOS:
- Navigate to WooCommerce > Settings > Advanced > Features
- Tick the High-Performance Order Storage (HPOS).
- Click Save changes.
Place a test order to make sure the placeholders in your notifications are now filled in correctly.