We were there last year and wanted to recharge our airbox (dongle) and the same with the mobile phone. I anticipated it taking 5 minutes; going in, say hello and here's my French orange mobile number, here is the sim card, quick recharge, out the door, done.
'Monsieur, yur zim card az expired and yoo must 'ave anozer.' Quoi?
Apparently because I hadn't used the mobile for a year it was disconnected. Now bearing in mind they had all my details I thought it a simple task of reconnecting. But no. Yes they could sell me a new sim card (couldn't have the existing one) but not without doing the ID check again, despite having all my details on file. So I took my wallet out and showed them the photo ID of my driver's licence. Malheuresement, that was not enough, they required my passport. So we had to drive 35km back home to get the passport. Anyway all sorted now and proud owner of a new French mobile number. I am, of course, now dreading that anyone French phones me as stumbling through grammar is bad enough face to face!