Why has the text autoprompt stopped working?

A column in my spreadsheet lists a selection of 10 or so names which will keep re-occuring each day down that column.

Each day I may need to enter lets say, Bananas in one row, Apples in the next, Pears the one after etc. (These are all entered in the same column). When I first started my list (I am now reaching the 500th row) Excel would automatically prompt a previous like name so that I would not have to finish typing the whole name. This was handy, for example when I typed 'ba' it would prompt 'bananas'.

Now, many names do not get prompted. Why is this? I don't think that it is because I have added more names and that some of the names are very similar and that there is nothing unique to prompt.

Bananas, Apples and Pears is just an example - the true names are quite long and there are quite a few, so it's not suitable just to copy and paste from cells above. I would have to search a fair bit.

If anyone can think of a way around this problem it would be handy. The auto prompting was very handy. Cheers.

Dan