You receive the error code 2101-0002 while using Nintendo Switch.
What to Do:
Restart the console by holding down the POWER Button for three seconds, then select "Power Options" > "Restart."
If the console does not respond, hold down the POWER Button for twelve seconds to force it to shut down. Then power it on again.
Ensure the console has the latest system update.
Situation Not Resolved:
If the error persists, the Nintendo Switch console will need to be repaired.
If you would like further assistance with the Nintendo Switch console, please contact Nintendo Customer Service.