The story, reported in newspaper Aujourd'hui, began when the woman, known as Meriem T, decided to switch mobile phone networks, from Orange to SFR.
The 46-year-old mother of three children from Châlons-en-Champagne in the east of the country, claims that she asked to keep her old number, but it was given to another customer who then started receiving her calls.
One of these calls was the offer of a job from a company in the Marne area which had already employed her and was offering further work, with the possibility of a permanent contract.
SFR admitted the mistake and, after giving the woman her old number back, offered her two free months subscription.
"It's too little given the damage that's been done," she told the newspaper. "I was waiting for that phone call, the company had said they would call in January if there was any work available."
"It's a missed opportunity," her lawyer said. "It's easy to offer a two month subscription…They can't treat their clients like that. They have to take responsibility."
The demand for damages of €200,000 have been calculated based on the salary she could have received for the job.