i got disconnect and later all i can see is that i lost on time.
Me too, but my internet works fine elsewhere..
Because your connection to the server is lost, but the server only sees your time go down and when it hits 0 you lose on time. It's only a game though and this is a free site, so don't worry about it and start a new one.
when maintenance is planned, it should be informed before starting a game.
the site is free as you said, but removing some issues it can be free and even better