My opened window from a button click close immediately

I am trying to click on a button inside a popup that will open a window to browse files, but when TestComplete click the button when running the Keyword Test, what happen is the following: the popup containing the button clicked close (as it should) and the window to browse files open and close immediately.

I am trying to do this in a python script that is executed in the Keyword Test. I tried ClickButton, Click, DoubleClick, but it all do the same. The button opening the window is in WPF.

If someone have an idea to keep the window open when it is opened by testcomplete, I would be thankful.