Images remaining vs images taken showing in playback mode - help!

[Oldshooter]

My A6400 has (today) started showing (in playback mode) the number of images taken on the current card rather than previously it was showing the estimated number of images remaining. I find the latter much more helpful! I'm guessing that I have accidentally changed a setting while I was swapping in and out various cards to format and free up space before a photo event next weekend. I've looked at the menus myself and have also tried the online manual and general googling, but can't seem to find the answer. I have cycled through the various 'Disp' options, but these don't change what is being displayed in terms of images taken.

Can anyone help?

Thanks!