Through its official support page, Nintendo has announced that there will be new maintenance operations for Nintendo Network services in the coming days. As you read on the site, "During the scheduled maintenance period specified below, some network services may not be available." Minecraft (Wii U and Switch): From Wednesday 31 May 2017 to 2:50 am until Wednesday 31 May 2017 at 4:30 pm Access using theNintendo Account (Switch): From Tuesday, June 6, 2017, from 2:00 pm to 6 June 2017 at 3:00 pm. We invite you to stay with us for any updates on the Nintendo world. Source: Nintendo