Is it an offence to be unreachable on a cell phone outside working hours?

Mr. [V] was hired as a truck driver on June 18, 2008 by the Transguy company.

Starting in June 2015, he was notified of several disciplinary sanctions.

He was finally dismissed for gross misconduct on January 16, 2018.

The employee brought an action before the industrial tribunal seeking the annulment of the disciplinary sanctions imposed on him, compensation for the damage he had suffered as a result of moral harassment, and an order that the employer pay him various sums in respect of the dismissal.