AD Group permissions not working

[pz7rx8]

I have an QNAP TS-EC1680U device that I have joined to Active Directory. I can see all domain groups and all domain users. I enabled Read/Write for the Public folder on an AD group and did not have any issues. When I check a domain user permissions, that is part of the AD group I enabled, it shows the Public folder as No Access and RW is not checked. If I check the Public Shared Folder permissions it shows Read/Write is enabled for the AD group the user is a member. As a result the user can not FTP to the shared Public Folder. If I change the user permissions and enable RW for Public FTP works fine. I have several hundred users and multiple folders, I do not want to have to enable permissions for each user.