This has happened to me a lot, unfortunately.
What browser or app (Android/iOS) are you using?
Well disconnecting is a very commonly used tactic to cause other players to react or to attempt to somehow manipulate the clock or game play during live blitz games. Losing connection sometimes can't be helped and if that causes a loss for ya ; then it kinda goes with the territory. And it happens to us all But if someone intentionally disconnects I think they kinda asked for whatever happens. Losing is as big a part of Chess as winning is. And it's my personal opinion ; that along with folks trying to get better and learning how to win more often ; people also need to learn how to lose with class & dignity.
I was playing a game and had a disconnect, but instead of waiting for the full amount of time to reconnect chess dot com said that I abandoned the game even though I had only disconnected for about 10 seconds. Usually for a 15/10 game 1 minute and 30 seconds are given to reconnect. I did have over 10 minutes on my game clock. Has this happened to anyone else?