This may be the root cause. It is listed in the Release Notes. Shipping Integration with FedEx: REST API Updates In NetSuite 26.1, the Shipping Integration with FedEx includes the following updates to comply with the FedEx Web Services Ship API upgrade: Multi-Factor Authentication (MFA) Required for FedEx Account Registration As part of the FedEx REST API upgrade, FedEx requires multi-factor authentication (MFA) to register and use your FedEx account in NetSuite. Existing FedEx accounts must be re-registered with MFA. Until MFA re-registration is complete, FedEx shipping label creation may fail. Using one of the available authorization methods (SMS, phone call, email, invoice details, or FedEx Customer Support), you'll receive a PIN to enter on the FedEx Registration page to complete authorization. Find the new Authorize your FedEx Account section on the FedEx Registration page at Setup > Accounting > Shipping > Add FedEx Account. For more information, see the help topic Registering a FedEx Account