Minecraft on Switch: We are still working on a fix. However, for a temporary workaround, try not signing in to a Microsoft account. While you won’t have access to servers, Realms, or possibly Marketplace content, you will be able to play single player & split-screen worlds. - HZ
Please send us an email at https://help.minecraft.net/hc/en-us/requests/new … and we will assist. Remember to attach your Transaction ID. ^SP