Lastminute.com - Rescheduled flight without permission

stevenshiels

I am wondering if anybody has come across my situation before, I've had a search of the forum but cant find anything similar. I had flights booked with Air France in April which were booked via lastminute.com and subsequently cancelled. After a couple of attempts at getting a refund I raised a claim dispute with American Express who refunded the transaction. 

This felt like case closed, but last week I received a notification from AMEX that Lastminute.com had successfully argued against the claim (they sent a T&C's document which blatantly shows that they are in the wrong but that's another story). 

This week I have received an email from Air France asking for passenger information for my flight next week, which I have not tried to reschedule or rebook in any shape or form! The flight is almost identical to those booked in April (same passengers, same days). So it looks like lastminute have rebooked the flights! There is now no evidence of the original booking (in current or past booking's) with LastMinute.com and I have no form of confirmation from Air France. 
 
The steps I have taken thus far are as follows: 
1. Re-open the dispute with AMEX.
2. Contact AirFrance to understand where the booking has come from. 
3. Attempted to contact Lastminue.com but cant get through on the phone, and their live chat does not accept my former bookingID. 

Does anyone have any further on advice on what I could do to protect my money, my fear is that by the time the dispute is action by AMEX, the flight will have happened and it will look like I'm a no show on a re-arranged flight I haven't booked. 

Any help would be greatly appreciated!