I ran into a similar issue, with the message:

Failed to log in: An unexpected error occurred. CAUSE: Unable to complete the operation. CAUSE: Error Domain=NSURLErrorDomain Code=-1005 "The network connection was lost."

Seems like a known issue with version 18.4 of the iOS Simulator according to https://community.auth0.com/t/auth0-swift-login-issues/186127

Downgrading to simulator version 18.3.1 solved the issue for me.