As company administrator, I am unable to change the roles of some of the users, what happen?

I'm delighted to have you here today.

Please know that I appreciate you for reaching out to us here in the Community space. I want to take of your concern directly on our page. To do so, may I know if you've encountered an error when trying to change the roles of some of the users? 

Any additional information will get us closer to the resolution and check if there's an open investigation about this. A screenshot would be a great help. Any extra information is appreciated.

I'm also adding this article below that contains details about the system requirements that work best for QBO with the usage limits: Learn about usage limits and what your best options are if you reach one.

I'll wait for your reply, or if you have any other questions, please let us know. We're always here to help. Have a great day.