Here's the Help & Support article:
https://support.chess.com/customer/portal/articles/1444849-why-did-the-clock-times-suddenly-change-the-clocks-seem-broken-
And here's one on lag:
https://support.chess.com/customer/portal/articles/1444918
Maybe try blitz instead?
Hi all you bullit games lovers. For some strange reason I almost fall short in time at the end of all my games lately. And I noticed that the time clock did crazy things at the end of all the games. I was leading in time and suddenly ~I was almost out of time. I was like a solid 1250-1350 player but now could hardly win against 1100 players. Is it my browser maybe that handles this system wrong. Okay sometimes I play bad and others play better, but not that often and I saw the clock do strange thing all in my disadvantage. Please help me because this is very frustrating. I use Firefox and safari as browsers on an Imac and both have the same problems.Thanks...