Kene Verbindung mehr.

Also ich habe in Google nur schnell "Nintendo Switch 2110-110" eingegeben und das erste Ergebnis war direkt ein Beitrag von der Nintendo-Support-Seite. Bin mal wieder überrascht, wie es sich manche Leute selber schwer machen. Naja, egal, anderes Thema.
Hier mal die Lösungvorschläge seitens Nintendo (ich gehe mal davon aus, dass Englischkenntnisse vorhanden sind):

Restart the Nintendo Switch console. To restart the console, press the POWER Button for three seconds, and then select "Power Options," followed by "Restart."
Check to ensure the Nintendo Switch console has not been placed into Airplane mode. Press and hold the HOME Button for at least one second to access Quick Settings and view the Airplane mode setting. Airplane mode must be disabled if you wish to connect to a wireless network.
Create a new wireless Internet connection file. When creating a new Internet connection, ensure your console is attempting to connect to the correct wireless network and that it is receiving a strong wireless signal.
Move the Nintendo Switch console closer to the wireless router. If possible, place the Nintendo Switch within 10 to 15 feet of the wireless router to improve the signal strength during troubleshooting.

It may be helpful to remove the Nintendo Switch console from the Nintendo Switch dock while troubleshooting, and then return the console when troubleshooting is complete.

Power cycle your home network. Restarting your network devices may resolve this issue if it is related to the devices being unresponsive.
Move any metal objects or electronic devices away from your Nintendo Switch console and wireless router. Metal objects and electronic devices may interfere with wireless signals. If you have any of these, such as filing cabinets, speakers, power strips, glass, or cordless phones, next to your system or wireless router, move them away.