after a few weeks of use, the small toggle switch on the side of the phone solves. An exchange took place on ensuring NOT !!!
Reason for refusal: the keyboard is mechanically damaged (was not the topic) even though it has not fallen down, or you're somewhere pushed against it.
An invoice is: 66.63 Euro repair costs. Replacement value of the equipment: about 35 Euro.
This is a customer-friendly response !!!