What is wrong here?

Error : Cannot assign of type [Result] to type Response

class NetworkManager: ObservableObject {
    var didChange = PassthroughSubject<NetworkManager, Never>()

    var data: Response{
        didSet {
            didChange.send(self)
        }
    }

    init() {
        guard let url = URL(string: "http://www.dqma.dk/football.json") else {
            return
        }
        let request = URLRequest(url: url)
        URLSession.shared.dataTask(with: request) { data, response, error in
            if let data = data {
                if let decodedResponse = try? JSONDecoder().decode(Response.self, from: data) {
                    DispatchQueue.main.async {
                        self.data = decodedResponse.data
                    }
                    return
                }
            }
        }.resume()
    }
}

struct Response: Decodable {
    var data: [Result]
}
struct Result: Codable {
    var match_id: Int
    var match_start: String
    var status: String
    var home_team: home_team
    var away_team: away_team
    var stats: stats?
}
struct home_team:  Codable {
    var team_id: Int
    var name: String
    var logo: String
}
struct away_team:  Codable {
    var team_id: Int
    var name: String
    var logo: String
}
struct stats:  Codable {
    var ft_score: String?
}

I'm new at this, but wondering if snake_case creates any problem, as I think Swift wants camelCase. Or does Swift need the variables appear in the order in which the JSON keys appear (even if you don't need to include all of them)?

This is the problem: self.data = decodedResponse.data

self.data is of type Response but you are assigning a Response.data, which is of type [Result].

self.data either needs to be of type [Result] or the offending line should be changed to self.data = decodedResponse, whicever works best for your use case.

I am suprised that it worked because the URL that you are using is not https and you should get this error

URLError: The resource could not be loaded because the App Transport Security policy requires the use of a secure connection