tomncrdbl

Internal Exception: io.netty.handler.coded.DecoderException: java.lang.NullPointerException: Cannot invoke "net.minecraft.network.ConnectionProtocol$PacketSet.m_178327_(int,net.minecraft.network.FriendlyByteBuf)" because the return value of "java.util.Map-get(object) is null thats the error code, does anybody know whats wrong?