Why am I unable to join minecraft nintendo switch world

Hi ItzEnder89

Sorry to hear about that, however, it seems that your sister is unable to host the game because if she can join you, then that means there's no issue on your end. So if you're both using the same internet source, that may mean that the bandwidth needed to play together are divided between of you which may cause intermittent connection.

You may try to ask her the NAT she's getting - she may want to restart her device or ask her to connect to a hotspot from a mobile data to see if it will suffice.

I can’t join online friends on Minecraft Nintendo switch

Here is a thread that might actually help with your issue: I can't join minecraft servers on nintendo switch - Microsoft Community

Hi Frankie. My name is Kyle and I'm an independent advisor.

I'm sorry you are experiencing issues joining worlds on Minecraft. Let me see how I can assist you.

What happens when you try to join a world? Are you receiving any error messages or error codes? If so, please provide them.

Keep in mind that online play on Switch requires a Nintendo Switch Online subscription.

Hello,

Thank you for contacting the Xbox Support forums. To better assist, I will need further details in terms of the error you are receiving. If I understand correctly, are you unable to access Minecraft on your new console? Did you already purchase Minecraft for the Nintendo Switch in the past?

You may also view Nintendo Switch Technical Support for a list of troubleshooting errors with Minecraft on Nintendo Switch.

Thank you,

-Tali