Game Center achievements are not saving or marking as completed.

I'm trying to implement Game Center in a SpriteKit game I am working on.

Leaderboards started working easily, but all the tutorials I could find online are either written in objc or are from 2015 or earlier I am using Swift 5 and Xcode 11.5. The achievements are set up on App Store Connect and everything works properly, except the achievements do not load and aren't getting marked as completed. Most of my Game Center code is in the GameScene.swift file, but the Game Center page is shown with the GameViewController file.

Here is my main Game Center code.

// MARK: Game Center
    func authenticateLocalPlayer() {
        let localPlayer: GKLocalPlayer = GKLocalPlayer.local
             
        localPlayer.authenticateHandler = {(ViewController, error) -> Void in
            if((ViewController) != nil) {
                // 1. Show login if player is not logged in
                GVC.present(ViewController!, animated: true, completion: nil)
            } else if (localPlayer.isAuthenticated) {
                // 2. Player is already authenticated & logged in, load game center
                self.gcEnabled = true
                     
                // Get the default leaderboard ID
                localPlayer.loadDefaultLeaderboardIdentifier(completionHandler: { (leaderboardIdentifer, error) in
                    if error != nil { print(error as Any)
                    } else { self.gcDefaultLeaderBoard = leaderboardIdentifer! }
                })
                 
            } else {
                // 3. Game center is not enabled on the users device
                self.gcEnabled = false
                print("Local player could not be authenticated!")
                print(error as Any)
            }
        }
    }
    func addPoints(pts: Int64) {
        // Add a point.
        score += pts
        // Submit score to Game Center leaderboard
        let bestScoreInt = GKScore(leaderboardIdentifier: LEADERBOARD_ID)
        bestScoreInt.value = score
        GKScore.report([bestScoreInt]) { (error) in
            if error != nil {
                print(error!.localizedDescription)
            } else {
                print("Best Score submitted to the leaderboard!")
            }
        }
    }
    func reportAchievements() {
        print(achievements)
        guard gcEnabled else {
            print("Game Center Not Enabled")
            return
        }
        GKAchievement.report(achievements) {
            error in guard error == nil else {
                print("""
                    
                    GKAchievement Error:
                    \(error as Any)
                     
                    """)
                return
            }
        }
    }
    var gcAchievements:[String:GKAchievement]? = nil
    func loadAchievements() {
        var allAchievements = [GKAchievement]()
        GKAchievement.loadAchievements(completionHandler: { (allAchievements, error: Error?) -> Void in
            if error != nil {
                print("Game Center: could not load achievements, error: \(String(describing: error))")
            } else {
                for anAchievement in allAchievements!  {
                    if let oneAchievement = anAchievement as? GKAchievement {
                        self.gcAchievements?[oneAchievement.identifier] = oneAchievement
                    }
                }
            }
        })
    }

This is called from elsewhere in GameScene.swift as:

achievements = []
achievements.append(AchievementName)
print(achievements)
print(AchievementName.isCompleted)
if A_leaveNosund.percentComplete == 0 {
     print("Rewarding for achievement completion...")
     A_leaveNosund.percentComplete = 100
     reportAchievements()
     addPoints(pts: 1)
}

(AchievementName represents my achievement's name, and is declared in the same class, earlier in the file).

Does anyone know what needs to be modified to make achievements load and get marked as completed in Swift 5?

Any help would be appreciated.

Thanks,

ajldev