Grid Based Movement System AI freezing?

In this code the AI will take a position in a queue to decide which player to attack, then decide the closest player and then decide the one with the lowest health, use path finding to find the shortest route there(Some tiles cost more action points to move through than others), then move towards the player it has decided to attack. But once the AI starts to make its move it freezes in place, and its position queue reverts to ZERO in the inspector. If i manually change its position queue back to 1 it will finish its move but its not just the one AI player, they all will sometimes act right and do what its supposed to do then sometimes in mid move it just freezes for no reason.. A short code snippet from my AIPlayer class. I have gone over it multiple times. It just needs fresh eyes, and any input you can give is helpful. thank you.

 public override void Update () {
         if(GameManager.instance.players[GameManager.instance.currentPlayerIndex] == this) { //If this is current player
     transform.renderer.material.color = Color.green; //Turn its material to green
         } else {
             transform.renderer.material.color = Color.white; //If not current player, turn its material to white
         }
         base.Update();
     }
     
     public override void TurnUpdate ()
     {
         if (positionQueue.Count > 0) { //If the position Queue is greater than 0
             transform.position += (positionQueue[0] - transform.position).normalized * moveSpeed * Time.deltaTime; 
             
             if (Vector3.Distance(positionQueue[0], transform.position) <= 0.1f) {
                 transform.position = positionQueue[0]; 
                 positionQueue.RemoveAt(0); 
                 if (positionQueue.Count == 0) { //if position queue count is at zero
                     actionPoints--; //spend action points
                 }
             }
             
         } else {
             //priority queue
             List<Tile> attacktilesInRange = TileHighlight.FindHighlight(GameManager.instance.map[(int)gridPosition.x][(int)gridPosition.y], attackRange, true);
             //List<Tile> movementToAttackTilesInRange = TileHighlight.FindHighlight(GameManager.instance.map[(int)gridPosition.x][(int)gridPosition.y], movementPerActionPoint + attackRange);
             List<Tile> movementTilesInRange = TileHighlight.FindHighlight(GameManager.instance.map[(int)gridPosition.x][(int)gridPosition.y], movementPerActionPoint + 1000);
             //attack if in range and with lowest HP
             if (attacktilesInRange.Where(x => GameManager.instance.players.Where (y => y.GetType() != typeof(AIPlayer) && y.HP > 0 && y != this && y.gridPosition == x.gridPosition).Count() > 0).Count () > 0) {
                 var opponentsInRange = attacktilesInRange.Select(x => GameManager.instance.players.Where (y => y.GetType() != typeof(AIPlayer) && y.HP > 0 && y != this && y.gridPosition == x.gridPosition).Count () > 0 ? GameManager.instance.players.Where(y => y.gridPosition == x.gridPosition).First() : null).ToList();
                 Player opponent = opponentsInRange.OrderBy (x => x != null ? -x.HP : 1000).First ();
 
                 GameManager.instance.removeTileHighlights(); //remove highlighted tiles once a move destination has been reached
                 moving = false; //make moving false
                 attacking = true; //make attacking true
                 GameManager.instance.highlightTilesAt(gridPosition, Color.red, attackRange); //highlight in red the tiles player can attack based on attack range
 
                 GameManager.instance.attackWithCurrentPlayer(GameManager.instance.map[(int)opponent.gridPosition.x][(int)opponent.gridPosition.y]); //attack the target in the tile that is chose
             }
 
             //move toward nearest opponent
             else if (!moving && movementTilesInRange.Where(x => GameManager.instance.players.Where (y => y.GetType() != typeof(AIPlayer) && y.HP > 0 && y != this && y.gridPosition == x.gridPosition).Count() > 0).Count () > 0) {
                 var opponentsInRange = movementTilesInRange.Select(x => GameManager.instance.players.Where (y => y.GetType() != typeof(AIPlayer) && y.HP > 0 && y != this && y.gridPosition == x.gridPosition).Count () > 0 ? GameManager.instance.players.Where(y => y.gridPosition == x.gridPosition).First() : null).ToList();
                 Player opponent = opponentsInRange.OrderBy (x => x != null ? -x.HP : 1000).ThenBy (x => x != null ? TilePathFinder.FindPath(GameManager.instance.map[(int)gridPosition.x][(int)gridPosition.y],GameManager.instance.map[(int)x.gridPosition.x][(int)x.gridPosition.y]).Count() : 1000).First ();
 
                 GameManager.instance.removeTileHighlights();
                 moving = true;
                 attacking = false;
                 GameManager.instance.highlightTilesAt(gridPosition, Color.blue, movementPerActionPoint, false);
                 
                 List<Tile> path = TilePathFinder.FindPath (GameManager.instance.map[(int)gridPosition.x][(int)gridPosition.y],GameManager.instance.map[(int)opponent.gridPosition.x][(int)opponent.gridPosition.y], GameManager.instance.players.Where(x => x.gridPosition != gridPosition && x.gridPosition != opponent.gridPosition).Select(x => x.gridPosition).ToArray());
                 if (path.Count() > 1) {
                     List<Tile> actualMovement = TileHighlight.FindHighlight(GameManager.instance.map[(int)gridPosition.x][(int)gridPosition.y], movementPerActionPoint, GameManager.instance.players.Where(x => x.gridPosition != gridPosition).Select(x => x.gridPosition).ToArray());
                     path.Reverse();
                     if (path.Where(x => actualMovement.Contains(x)).Count() > 0) GameManager.instance.moveCurrentPlayer(path.Where (x => actualMovement.Contains(x)).First());
                 }
             }