Is Air France open on 24/7?

Yes, Air France is open 24/7 and offers worldwide customer support ¹
Passengers can call them directly at +1-804=853=9001 (USA) or
+1-804=853=9001 (UK) ¹. Here are the steps to connect to Air France ¹:

Dial the Air France customer service number.
Press 1 to know about Air France services.
Press 2 to know about flight reservations.
Press 3 to know about flight status.
Press 9 to speak to a customer service representative.

Source: https://community.expensify.com/discussion/13990/customer-support-is-air-france-open-on-24-7-helpline/p1?new=1