I was trying to run my project using npx expo start --tunnel so i could use the expo go app but was facing the same issue , after i scanned the QR code it was just loading and read out an error message in the end.

to fix this error, you just need to make sure your phone and your computer are on the same network, if they are and its still not working , just go to your Wi-Fi settings on you computer and switch to private network where your device is discoverable.

if you done that just run npx expo start, you don't need to add --tunnel and it should work.