See explanation below.
* Navigate to System administration > Security > Assign users to roles
* Select the 'Accountant Closing' role.
* Click the "Manually assign / exclude users" button
* Select the Theresa Jayne user account and click the "Assign to role" button.
* Click the "Assign organizations" button
* Select the "Grant access to specific organizations" option
* Select the USMF legal entity and click the "Grant" button.
Reference:
https://www.dynamics-tips.com/system-administration/security-roles