RDP webapp connecting to incorrect server

Hi All,

I have configured Remote Desktop Services on our branch office. Both main office and branch office has RDP ports forwarded. On branch office, I have forwarded RDP port to the remote desktop server and in main office it's forwarded to a different server.

For some users when they are accessing from outside using https://<public_ip_Branchoffice>/RDWeb and after login when they try to open awebapp it is trying to open that app using the main office server (which I have forwarded RDP port using the main office firewall). But for some users it does work fine (they are directly connected to the RDS server in the branch office).

Is there a way that I can stop Remote WebApps trying to connect to the main office firewall and only connect to the branch office firewall so it will be forwarded to correct server?

And what is the reason for some users to work not to work for others?

Thanks.