iOS26 UINavigationBar small title not visible when scroll

I have an App with a UITabBarController. When one of the Tabs is selected then it presents a UINavigationController. This in turn presents a UIViewController to start with. (Call it myViewVC)

myViewVC has a UITableView. This is the only subview of myViewVC.

When I scroll I expect the UINavigationBar to collapse from a large Title to a small title. But instead I see no small title. This all worked fine in iOS18.x

I have tried various things suggested on forums and by AI and none of these have fixed the problem

1. I have set both self.navigationItem.title = @"My VC"; and self.navigationItem.largeTitle = @"My VC (New in iOS26)

2. It was suggested that I tie the UITableView constraints to the top of the view rather than the safe area. That did not help.

3. I have removed any custom appearance settings for the UINavigationBar. That did not help.

4. I also tried to add this line but it did not help

myTableView.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;