You and your opponent each have their own clock. Yours is shown below the board, your opponent's is above. In this game https://www.chess.com/game/live/142359706498?username=geelongcats65 which I think is the one you are talking about, your clock has run down to 0, so you ran out of time. Your opponent still has 11:40 minutes. So you lost.
I lost a match not loosing a piece
Thanks for explaining that to me smallpawninabigworld I can learn from that for the next thankyou to all the other's who commented cheers.
I think I'm understanding so if you take longer to make moves your clock runs out first and that's why you loose is that correct