WooCommerce integration with MYOB AccountRight frequently fails during API sync

We are currently experiencing an issue with our WooCommerce integration with MYOB AccountRight on the website using the OPMC plugin.

While the initial connection and validation work correctly, the plugin frequently fails during API syncs or token refresh with intermittent 401 errors.

We initially assumed no firewall was in place. However, upon further investigation and external scans, it’s clear that the server is behind a WAF (Web Application Firewall), likely powered by OpenResty.

How do we allow the connection to the MYOB API server established for this integration to work?

Any assistance or advice is greatly appreciated.