C# ObservableCollection not adding items to TabbedPage's ListViews

I have a method returning a List to set a ListView's ItemSource. Here are the exact calls of the nested lists.

Here is the call of the TabbedPage

`public ItemsMainTabbedPage(ObservableCollection sortedItems)
{
InitializeComponent();

for (int i = 0; i < 3; i++)
{
    ItemsPagePro page = new ItemsPagePro(sortedItems, i);
    this.Children.Add(page);
}                         

}`
Here is the ItemsPagePro where is ListView is set

`public ItemsPagePro(ObservableCollection sortedItems, int switcher)
{
InitializeComponent();
switch (switcher)
{
case 0:
Title = "Home";
listView.ItemsSource = getTabbedListResults(sortedItems, (int)TabLoadMode.All);//0
break;
case 1:
Title = "Safe";
listView.ItemsSource = getTabbedListResults(sortedItems, (int)TabLoadMode.Safe);//1
break;
case 2:
Title = "Risky";
listView.ItemsSource = getTabbedListResults(sortedItems, (int)TabLoadMode.Risky);//2
break;
}
}

private ObservableCollection getTabbedListResults(ObservableCollection sortedItems, int switcher)
{
var itemsSource = sortedItems;
ObservableCollection sortedItemsMain = new ObservableCollection();
ObservableCollection items = new ObservableCollection();
try
{
bool safe = false;
if(switcher == 1)
{
safe = true;
}
for (int i = 0; i < itemsSource.Count; i++)
{
for (int j = 0; j < itemsSource[i].Count; j++)
{
if(itemsSource[i][j].multiPassedMatchesHTML != null)
{
if (!string.IsNullOrEmpty(itemsSource[i][j].multiPassedMatchesHTML.HTMLToParse))
{
itemsSource[i][j].DetailedTips = SampleDataSource.getDetailedTips(itemsSource[i][j].multiPassedMatchesHTML.multiPassedMatches, safe);
if (itemsSource[i][j].DetailedTips != null)
{
if (itemsSource[i][j].DetailedTips.totalMatches > 3)
{
bool checkResults = checkBeforeResults(itemsSource[i][j]);
if (checkResults)
{
itemsSource[i][j].Tip = SampleDataSource.getHighestResultFromMultiPassedMatches(itemsSource[i][j].DetailedTips);
itemsSource[i][j] = switchItemTip(itemsSource[i][j]);
//if (switcher != 0)
//{
items.Add(itemsSource[i][j]);
Console.WriteLine("Item added!");
//}
}
}
}
}
}
}
//if(items.ToList().Count > 0)
//{
sortedItemsMain.Add(new Titles(items.ToList()) { Intro = itemsSource[i].Intro, imagePath = itemsSource[i].imagePath, Summary = " - " });
//}
//items.Clear();
}
if(switcher == 0)
{
return itemsSource;
}
else
{
return sortedItemsMain;
}
}
catch(Exception ex)
{
DisplayAlert("Error:", ex.Message, "OK");
return null;
}
}`
It is driving me crazy. As I am finding out, this line is messing it up. itemsSource[i][j].Tip = ... When i try changing it's value(string), without any error it messes up the rest and the other listview in the other tabs are empty.

Any idea why?