Bug report - Navigation prompt screen stuck

Hello, 

When using Software Version 9.11 the Navigation prompt stuck often.

For example, it shows a zoom screen with the coming junction and a timer until I get there, and after a while the time is stuck and the screen remaining also after I pass the junction.
The only way to close it is to unlock the touch screen and press the X in the corner.

I think this is a bug.

By the way, in some junctions the navigation prompt  screen appears and in others it doesn't.
Could someone clarify in which junctions the navigation prompt screen appears and when it doesn't?

Thank you!