Why won't some cells remain left justied in excel 2003

[mr. charlie brown]

In Excel 2003, I input a date in one cell and a title in another cell on tab
1. Each of the other 20 tabs have one cell formulated to pick up the date
and one cell formulated to pick up the title in tab 1. I have formatted all
of these cells to align left justified. However, everytime I check each
tab, several of the cells will have switch to "center". It happens randomly,
not always the same tabs.

I have realigned the cells, copied a new cell over it and reset the formula,
aligned the entire row left justified, but continues to happen.

Thanks in advance!