Remember to save UserInfo to fileManager, before attempting to retrieve any data

Retreive UserInfo from FileManager.swift

    func retrieveUserInfo() throws -> User {
        
        let plistDecoder = PropertyListDecoder()
        let filePath = FileManager.documentsDirectory
        let file = filePath.appendingPathComponent("SavedUserData").appendingPathExtension("plist")
        guard let retrievedData = try? Data(contentsOf: file) else { print("Errors: \(Failure.missingFile.errorDescription)"); throw Failure.missingFile }
        guard let decodedUserData = try? plistDecoder.decode(User.self, from: retrievedData) else { print("Error: \(Failure.failedDecodingFile.errorDescription)"); throw Failure.failedDecodingFile}

        return decodedUserData
    }