MMCobra

Hello. I am having problems accessing multiplayer mode using a modpack called "Cobblemon Realms" to which I added some external mods. The game itself starts but the multiplayer lan or server does not work, giving me this error code [Render thread/WARN][net.minecraft.client.multiplayer.ClientCommonPacketListenerImpl/]: Client disconnected with reason: Disconnesso/a Can you tell me how to fix it or help me yourself?