Xcode 15 b6 - "The network connection was lost" in Simulator

Hello, I'm working on SwiftUI app where I'm trying to access ReST API. When I run may app in Simulator, I'm getting "The network connection was lost", but it's working without issues on physical device.

struct ContentView: View {
    @State var jednotky: Jednotky = Bundle.main.decode("jednotky.json")
    @State private var isOffline = false
    
    var body: some View {
        NavigationView{
            VStack{
                List(jednotky.rootLevel, id: \.id) { item in
                    NavigationLink{
                        SoutezeView(rocnik: 2023, jednotka: item.childId, nazev: item.nazev)
                    } label: {
                        JednotkaRowView(nazev: item.nazev, childId: item.childId, parentId: item.parentId)
                    }
                }
                
                if (isOffline) {
                    Text("Using offline data")
                }
            }
            .navigationTitle("Fotbal")
            
        }.onAppear{
            Task{
                await loadData()
            }
        }
        
    }
    
    func loadData() async {
        let url = URL(string: JEDNOTKY_URL)!
        var request = URLRequest(url: url)
        
        guard let authData = (USERNAME + ":" + PASSWORD).data(using: .utf8)?.base64EncodedString() else {
            print("Can't create authorization header")
            return
        }
        
        request.addValue("Basic \(authData)", forHTTPHeaderField: "Authorization")
        
        do {
            let (data, _) = try await URLSession.shared.data(for: request)
            if let temp = try? JSONDecoder().decode(Jednotky.self, from: data) {
                jednotky = temp
            }
        } catch {
            print("Cannot download data, using stored sample instead")
            isOffline = true
        }
    }
}

The error in console:

nw_socket_handle_socket_event [C1.1.1:3] Socket SO_ERROR 9
Connection 1: received failure notification
Connection 1: failed to connect 1:9, reason 18 446 744 073 709 551 615
Connection 1: encountered error(1:9)
Task <103A0196-6715-429B-A5F2-79698C6E9D45>.<1> HTTP load failed, 0/0 bytes (error code: 18 446 744 073 709 550 611 [1:9])
Cannot download data, using stored sample instead
Task <103A0196-6715-429B-A5F2-79698C6E9D45>.<1> finished with error [18 446 744 073 709 550 611] Error Domain=NSURLErrorDomain Code=-1005 "The network connection was lost." UserInfo={_kCFStreamErrorCodeKey=9, NSUnderlyingError=0x600000c03d50 {Error Domain=kCFErrorDomainCFNetwork Code=-1005 "(null)" UserInfo={_NSURLErrorNWPathKey=satisfied (Path is satisfied), interface: en0[802.11], _kCFStreamErrorCodeKey=9, _kCFStreamErrorDomainKey=1}}, _NSURLErrorFailingURLSessionTaskErrorKey=LocalDataTask <103A0196-6715-429B-A5F2-79698C6E9D45>.<1>, _NSURLErrorRelatedURLSessionTaskErrorKey=(
    "LocalDataTask <103A0196-6715-429B-A5F2-79698C6E9D45>.<1>"
), NSLocalizedDescription=The network connection was lost., NSErrorFailingURLStringKey=https://is.fotbal.cz/api/jmobile2/orgJednotky.aspx, NSErrorFailingURLKey=https://is.fotbal.cz/api/jmobile2/orgJednotky.aspx, _kCFStreamErrorDomainKey=1}