I have attached a very simple project demonstrating a bound tab control. Upon a button click, an item is inserted in the tabs collection of the view model and the tab control immediately creates a new tab for the new item. Do give it a try and see how it goes.
I am unsure how you have implemented this in your actual application, but I hope that you will be able to find the differences with the project I sent and adopt the same approach. If you need further assistance with this, please modify the project to mimic your set up and to reproduce the behavior so that we can investigate it.
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