Page unavailable (Debian 9, seafile-pro-server_6.3.9_x86-64)

I want to test seafile-pro-server. I have successfuly installed the server and also started, but when I want to work client applications (seafile-gui and seadrive) can not make connection and on the server’s web page I can read: “Page unavailable. Sorry, but the requested page is unavailable due to a server hiccup.”
In the terminal I can read that sever was started correctly:

vlado@debian-test:~/seafile/seafile-pro-server$ ./seafile.sh start

** Message: seafile-controller.c(1155): loading seafdav config from /home/vlado/seafile/conf/seafdav.conf

[05/30/19 10:17:27] …/common/session.c(139): using config file /home/vlado/seafile/conf/ccnet.conf
[05/30/19 10:17:27] …/common/license.c(406): Loading license file /home/vlado/seafile/seafile-license.txt …
[05/30/19 10:17:27] …/common/license.c(409): License file /home/vlado/seafile/seafile-license.txt does not exist, allow at most 3 trial users
License file /home/vlado/seafile/seafile-license.txt does not exist, allow at most 3 trial users
Starting seafile server, please wait …
** Message: seafile-controller.c(1155): loading seafdav config from /home/vlado/seafile/conf/seafdav.conf

Seafile server started

Done.
vlado@debian-test:~/seafile/seafile-pro-server$ ./seahub.sh start

LC_ALL is not set in ENV, set to en_US.UTF-8
Starting seahub at port 8000 …

Seahub is started

Done.

Solved for now. I had to restart the virtual server (debian 9).

Hi Vladimir,
please mark your threat as “solved”.
Thanks