Background service alamofire swift ios - ios

Question

I have to call method that retrieve data from server every hour in background. For instance when click home button disappear app. Then run code every hour and send local notifications. My code is
#objc func getCustomerOrders() {
let headers = [
"accept": "application/json",
"Username": "info#bse.com.cy",
"Password": "1234"
]
Alamofire.request("https://leathermaster.bse.com.cy/api/getcompletedorders", method:.get, encoding: JSONEncoding.default, headers: headers) .responseJSON { response in
switch (response.result) {
case .success( _):
do {
self.orders = try JSONDecoder().decode([OrderComplete].self, from: response.data!)
if self.orders.count > 0 {
for i in 0...self.orders.count-1 {
if self.orders[i].PhoneNumber == self.preferences.string(forKey: "phone") {
print("TransactionStatus \(self.orders[i].TransactionStatus)")
let date = self.orders[i].TransactionDate.date.replacingOccurrences(of: ".000000", with: "")
let center = UNUserNotificationCenter.current()
let content = UNMutableNotificationContent()
content.title = "\(self.preferences.string(forKey: "firstname")!) \(self.preferences.string(forKey: "surname")!) your order with \(self.orders[i].TransactionCode) transaction code is ready for pickup"
content.body = "\(self.orders[i].TransactionStatus) Date Time: \(date)"
content.sound = .default
content.userInfo = ["value": "Data with local notification"]
let fireDate = Calendar.current.dateComponents([.day, .month, .year, .hour, .minute, .second], from: Date().addingTimeInterval(20))
//let trigger = UNCalendarNotificationTrigger(dateMatching: fireDate, repeats: true)
let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 3600, repeats: false)
let request = UNNotificationRequest(identifier: "reminder", content: content, trigger: trigger)
center.add(request) { (error) in
if error != nil {
print("Error = \(error?.localizedDescription ?? "error local notification")")
}
}
}
}
}
} catch let error as NSError {
print("Failed to load: \(error)")
}
case .failure(let error):
print("Request error: \(error.localizedDescription)")
}
}
}
let notificationCenter = NotificationCenter.default
notificationCenter.addObserver(self, selector: #selector(getCustomerOrders), name: UIApplication.willResignActiveNotification, object: nil)
I try to run code when app is closed and send periodically local notifications in swift iOS. I hope to give me a solution an expertise programmer.