Failed to login or play off line for DOW2 Retribution

GForce01

Just bought DOW2R and a dozen of DLCs on Steam.
When I start the game today I did reach the main screen alright but thought my net connection is working fine the game only shows 'disconnected from steam server'
Also, the Okay button won't work for the popup window of offline notice when I clicked the campaign tile, so the game basically stuck there, neither can I press the button and play offline nor can I manage to close the window.

I do need some help with this, can't really play the game

GForce01

Well in fact I did managed but only once to play the game, that happened when I first registered this community account and immediately start the game when a steam popup window appeared and shown me to login with my account. After that it seems to be the only time the game appears to be 'connected to the server', no notice popped up when I clicked campaign and I play the game for the only time.