Strange behaviour during navigation

Hi,

I planned a trip and the app calculated correctly choosing highways when available, but while driving it starting to behave erratically trying to hook nearby roads thus changing every estimation of ETA, SOC at arrival etc.
I made the trip back and forth (circa 600km per leg) and the oddity was the same in both directions in the same areas.

Tried to navigate same zones with iOS Maps and built-in car navigator and it worked flawless, so i reckon ther were no GPS issues

This is the area where te issue appears:

Regards,

Francesco