Reset FNC Grid

I have a small FNC Grid which needs to be cleared and refilled based on selecting an item from a listbox. Bofore the the new content is added to the grid I resest it with the following code:

FNCGrid_general.ColumnCount := 2;
FNCGrid_general.Columns[0].Width := 200;
FNCGrid_general.Columns[1].Width := 150;
FNCGrid_general.RowCount := 1;

Unfortunately this does not clear the previous content and the new content is added at the bottom. What do I need to do differently?

Please Disregard - The error was in a list feeding the grid which was not cleared before and thus appending info