IOS/SWIFT4 - HTTP load failed (error code: -1005 [4:-4]) - ios

Question

Does anybody know what HTTP load failed (error code: -1005 [4:-4]) is? I saw a few answers on here, some say it's that the server can't process more than x requests at a time, others say its alamofire.
My script refreshes every 60 seconds and there is only one request at a time. I have alamofire installed in my project, but not using it for this refresh.
It works the first few times, but after a few minutes i get this 1005 error and then it never again afterwards unless i go to a different page and come back.
URLCache.shared.removeAllCachedResponses()
if let requestURL = URL(string: "https://www.example.com/file.php") {
var urlRequest = URLRequest(url: requestURL)
urlRequest.httpMethod = "POST"
let postString = "username=\(Username.text!)&password=\(Password.text!)&device_token=\(device_token)"
urlRequest.httpBody = postString.data(using: .utf8)
let session = URLSession.shared
let task = session.dataTask(with: urlRequest as URLRequest) { (data, response, error) in
if let data = data {
do {
if let jsonResult = try JSONSerialization.jsonObject(with: data, options: []) as? [String:Any] {
// get lots of vars here
// Async Stuff
DispatchQueue.main.async(execute: {
// do lots of things here
})
}
} catch {
print("Error: \(error)")
}
}
}
task.resume()
}
The error goes like this:
TIC Read Status [2:0x60400016bac0]: 1:57
... HTTP load failed (error code: -1005 [4:-4])
... finished with error - code: -1005
• I tried to add session.reset(completionHandler: { print("session ended") }) at the end
• In another post i read that i should add a header-length. but not sure if i should do that on the server or the Xcode project?
• And somehow i can't catch this error and trigger something else.