Not retrieving any messages!

 (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];

    PFQuery *query = [PFQuery queryWithClassName:@"Messages"];
    [query whereKey:@"senderName" equalTo:[[PFUser currentUser] objectId]];
    [query orderByDescending:@"createdAt"];
    [query findObjectsInBackgroundWithBlock:^(NSArray *objects, NSError *error) {
        if (error) {
            NSLog(@"Error: %@ %@", error, [error userInfo]);
        }
        else {
            // We found messages!
            self.messages = objects;
            [self.tableView reloadData];
            NSLog(@"Retrieved %d messages", [self.messages count]);
        }
    }];
}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    // Return the number of sections.
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.
    return [self.messages count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    PFObject *message = [self.messages objectAtIndex:indexPath.row];
    cell.textLabel.text = [message objectForKey:@"senderName"];

    NSString *fileType = [message objectForKey:@"fileType"];
    if ([fileType isEqualToString:@"image"]) {
        cell.imageView.image = [UIImage imageNamed:@"icon_image"];
    }
    else {
        cell.imageView.image = [UIImage imageNamed:@"icon_video"];
    }

    return cell;
}
#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    PFObject  *messages = [self.messages objectAtIndex:indexPath.row];
    NSString *fileType = [messages objectForKey:@"fileType"];
    if ([fileType isEqualToString:@"image"]) {
        [self performSegueWithIdentifier:@"showImage" sender:self];
    }else{

    }

}