cheat with time

What likely happened is that you had a brief disconnect and the server may not have received your move.
The server is the keeper of the accurate time. With the lag compensation algorithms the times on the clients may not be accurate. That is why you may occasionally see clocks adjusted in games, even without increments.

for the second time i noticed that during the end game the time of my opponent kept jumping back to higher a number of seconds left. very annoying and unfair.

for the second time i noticed that during the end game the time of my opponent kept jumping back to higher a number of seconds left. very annoying and unfair.

So just play a different person who doesn't cheat
They weren't cheating in the first place
Chess.com uses Fischer delay for the incremental time controls. For example, if you are playing a 2 minute game with 2 seconds added to the clock after each move (2 2), then it's possible for the person to move quickly enough to add time to their clock.

Yes it is a cheat only accessible to Diamond users. They can add or remove seconds to the clocks as they wish. It's unfair, like life itself.
This is just not true. No-one can add or remove seconds, whatever their level of membership. The only time advantage that diamond membership earns is that in daily chess it automatically puts you into vacation mode if you do not make your move within the permitted number of days.

Yes it is a cheat only accessible to Diamond users. They can add or remove seconds to the clocks as they wish. It's unfair, like life itself.
This is just not true. No-one can add or remove seconds, whatever their level of membership. The only time advantage that diamond membership earns is that in daily chess it automatically puts you into vacation mode if you do not make your move within the permitted number of days.
He was joking dude

Well im used in facing different cheaters (in bullet games, i was 14++) :
the magic time (to play fast vs a weak opponent and suddenly, hes got a lot of time)
the magic moves (to play well vs a weak opponent and suddenly hes got a lot of good moves)
the magic mouse (suddenly my mouse dont answer well, its hard to select pieces)
...
disapointed and tempted by deleting my account...

Discussions of cheating and/or accusations are not allowed in the general forums. If you would like to discuss that, join the following group:
https://www.chess.com/club/cheating-forum (v3)
https://www.chess.com/groups/home/cheating-forum(v2)
You can report suspicions of cheating here:
https://support.chess.com/customer/portal/emails/new
And check out the following.