Not retrieving data in a MDK Extension Control

[Alexandre-G]

Hello everyone,
I'm currently developing an application using mobile development kit client 
My goal was to display a map on the application and use the longitude and latitude of a location to display it. I've followed this tutorial :Extend Your MDK App With a Map Custom Control (Using Metadata Approach) | SAP Tutorials
But i can't retrieve my data in my extension, there is my page :

Above, my map extension, just below, two Key Value Items where I retrieve longitude and latitude data. The extension and Key Value Items have the same target path. However, the Key Value Items work correctly and retrieve the data. As for the extension, even though it has the same target path as the input, it doesn't retrieve the data, so I can't display the map.

Thanks in advance !