I can't login with the same connection i was playing from day 1-this patch

It doesn't connect and it say connection error but i played the game with same connection from day 1 until end of Yuki's patch. When traffic on my network is low it works but that 3/2mbs. The game was working perfectly fine with mediocre internet , now it doesn't. The problem is even if i get in it just pops "invalid connection error"this in every few seconds.