Can you please give access to one of our user who had full access but it has been restricted for few weeks?

Thanks for reaching out to me here in the Intuit Community, @dorota999.

Only the Accountants or Master Administrators have the capability to change a user's access rights in QuickBooks Online.

If you're the Master admin, here are the steps on how to edit the user's access:

1. Go to Your Practice.
2. From the left pane, select Team.
3. Click the user you want to change its access. 
4. Go to the Firm Administration and Books tab.
5. Select Full from the Access drop-down.
6. Click Save. 

For additional information with the solution above, you can go through here: How to manage users in QuickBooks Online Accountant.

Should you need anything else concerning user access, please let me know by leaving a message below. I'm always around whenever you need help.