Answer:
(I am not fluent in French, but here is what I interpreted) The problem is alcohol usage
Step-by-step explanation:
The problem is his excessive use of alcohol causing a mistake at work
His friend Mehdi is concerned
It doesn't state when the addiction started and only that the mistake at work happened recently
Stephen is now seeing an addictilogist
The problem is getting worse because he wouldn't acknowledge that he had a problem