Missing VPN token field

I am using FortiClient to connect to a VPN that requires a token for authentication. This works well only the first day (or before the first reboot), next day it doesn't show the popup to enter the token. I also noted that it stops showing system notifications. I have to reinstall FortiClient every day to make it work. I am using Xubuntu, but tried on Windows as well and something similar happens, it stops showing the token field.