I have had one issue happen twice.

Last Nov I booked a ticket to personal card, and it charged to my expense card, I thought ok this is a fluke and I did something wrong. Well, it did it again last week now.

I normally book on the card that card, but for some leisure trips I prefer not to have to report all those costs to finance dept

However, its done the same thing twice now and 100% sure this time that I did it to my personal leisure card, yet still went to my expense card.