Did the OP find a solution to this, I have been Googling in desperation and ended up here.

I have exactly the same problem, it's not a screen refresh issue as it works as it should on 3 out of 4 of my worksheets in the same file (ie the text/data in the cell above is visible as I type in the cell below). On one worksheet only, when I type in one cell, the data in the cell above is blanked out. This is a small file, 30k and has no formulas in it apart from some autosums (I am doing my personal business accounts for a very small business).

Am worried I have somehow hit a keyboard shortcut by mistake and that somewhere down the line the cell data is going to be wrong when I come to start adding all the figures together.

Any ideas? Excel is my least favourite software, seems you can make one mistake and then it's pretty much impossible to figure out what you've done?