I have a formula in a cell which counts the values in 2 other cells. Normally, after entering in the values in these 2 other cells, the formula cell updates automatically when `Enter` is pressed or when the cells are clicked out of.

However, for some reason, the value calculated by the formula does not update automatically. I am having to click on the formula bar, then I have to click enter for the formula cell to do its thing.

Why is this happening?