If you are facing any transaction errors, and not sure what is causing the issue, best to look for error in the order below.
Files:
- public_html/wp-content/uploads/wc-logs
- (each transaction is saved as a separate file)
- Alternatively, can look in WordPress Admin > Woocommerce > Status > Logs
- public_html/error_log
- default apache error / notice log
- public_html/wp-content/debug.log
- wordpress debug log
(Assuming your web root is public_html)
Other places:
- /var/log/
- this is the server wide collection of all errors. You won’t have access to this through a user account; likely need to log in as root
Sources: https://docs.woocommerce.com/document/finding-php-error-logs/