This error could be related to your own connection. Have you tried playing on wifi? This will probably solve it. There is a signal strength icon in the upper right corner in the game during battle. Please make sure you have full 4 green-color bars, which indicates you have a good signal strength and ping speed. Less than that or other color indicates your connection is not strong enough to have a good play experience. The game will actually prevent you from entering a match if your signal is not good enough, or it could take you out of the match if during the battle your signal strength becomes weaker, making it difficult to complete the match. This is for your own best experience and that of other players. Please try with a different connection and let us know how it goes.