There are circumstances when errors occur as a result of there being heavy traffic to the servers due to the nature of the Internet, as a result of other processes your device is running causing the app not to function properly, or other causes.
The issue may improve if you try the following.
■ Things to try
・ Close any browsers and tabs you have open.
・ Restart your device.
・ If you can access the app's starting screen, tap Menu, then tap Clear Cache.
・ Delete unnecessary images or videos to free up memory space on your device.
・ Reinstall the app.
Note: Please check that your save data is linked to your Nintendo Account.
Please note that, depending on your device, the steps to perform the above operations and the language used may differ from what is described above. Please refer to your device's user manual or customer support website for additional information.
If the above steps do not resolve your problem, it is possible that your network connection status is influencing the situation, so please check the Internet setup you are using.
・ Try using a 4G connection from a location that is out of range of the Wi-Fi network you normally use.
・ Try using a network that is connected to the Internet that is different from the one you normally use.
Also, if you are using content blockers (ad-blocking apps, software, or VPN apps), please try turning them off temporarily.
If you have changed your HTTP proxy settings, please revert them.
If the above does not resolve your issue, please contact Customer Support via the Inquiries form at the bottom of the page.