Please do not post in all upper case letters - it makes you post harder to
read and it is considered to be shouting.

For autocomplete to work there must be a continuous connected path of cells
with data in between the new entry and the previous entry of that same data.
E.G. If you have data in B1:B10 and you start to enter the same data as B1
in B12, autocomplete will not work because the entry cell in isolated from
the data.  If however there was a continuous set of data in column A - say a
series of dates down to A12 - then autocomplete will work because it is
*connected* to the original data.