Hi Jean,
Thank you for contacting Syncfusion Support.
We have analyzed your query with your sample application. In that you have declared the style for TextBlock in first page and you have tried to use that style in both the pages as a static. Hence the exception occurred, since it is defined in MainPage.xaml alone. However you can declare the Style Globally in App.xaml and it can be accessible in all pages. We have modified the sample based on this and please find the sample under the following location,
Sample:
http://www.syncfusion.com/downloads/support/directtrac/141092/ze/SyncfusionBindingError-1113224283
Please let us know if you need further assistance.
Thank you,
Jai Ganesh S