Playing Heroes of Might and Magic V on Ubisoft servers.

There are some strange lags, the password isn't accepted, I change it, and in one game everything is okay, but when I log in again, the password isn't accepted. I decided to play with a friend in the "Hammers of Fate" faction, I enter the key, and it says that it's invalid. P.S. Now I logged into "Necropolis," and I can't join; it says that the checksum of something doesn't match the checksum of something else. Error code 0.2.0. Please check the patches and mods. I can't join, and others can't join me. Patch 3.1, no mods installed.