Unable to activate Uipath Studio Trial

Despite the fact machine has whitelisted my.nalpeiron.com TCP 80 http (Services the Robot Connects to), during activation, there is a warning about unable to connect to activation server.
Offline activation returns an error about expiring license despite the fact it is first activation of a trial.
What may be the problem? We have already made a ticket for offline activation issue but we would like to use an activation server online. What else should be enabled?