Hi Paulas,
Thanks for your post.
I understand your concern about your staff being unable to create and update sales orders during a locked period in MYOB AccountRight. It's possible that the issue might be related to the user permissions set in your MYOB AccountRight. As an administrator, you have full access to all features, which might explain why you can alter orders during a locked period.
With this, I highly recommend checking the user access of the impacted staffs who are unable to create and edit sales order. You may check the Help Article: Set up roles for more information regarding your concern.
Feel free to post again anytime if you require further assistance.
If my response has answered your inquiry, please click "Accept as Solution" to assist other users in finding this information.
Best regards,
Doreen