Hello,
had same problem 3 weeks ago for a booking via Airfrance.fr. Once CC details filled in and I accepted. We have in FR to open the banks app on the phone to confirm the transaction which I did, and it said ' authentication confirmed', put a green mark on the website and went on the reservation details page where there was the PNR, passenger’s names etc. But I found it strange that no ticket number was shown and also no total amount as usual and the fare rules were greyed out. I called my bank as I thought I have a CC problem but they said that no transaction was done only the identification! I learned something new.
I then called AF and they explained that the "booking" has been made but the payment didn't go thru. So I gave her over the phone my CC details, they send a link directly why on the phone with them which opens the dialing pad on the phone and you have to type your CC again and immediately my booking details referring to amount, rules and ticket number appeared.
By the way, if you do a dummy booking on AF until the payment page, it automatically gives you a booking on hold for 24h which you only find if you are connected with you FF number under "my reservation".