Hausemaster and the others that run 2b2t.org have recently been changing the anticheat which 2b2t is running on constantly in an effort to allow all Vanilla gameplay mechanics and also prevent lag, however the anticheats which Hause is choosing to use are either interfering with Vanilla gameplay heavily and kicking players for false positives all the time, or are heavily broken and still allow gamebreaking bugs/exploits. My suggest for this is simply to go back to using NCP and just disable Elytra and rideable pigs. Many of us are used to no Elytra now on 2b2t and riding pigs was never a big deal and was more of a gimmick in Minecraft itself before EntitySpeed.