Editing Cell Notes

I have a worksheet that I have added notes to many different cells. Now I find I am unable to edit the notes and the typical red arrow at the top of the cell right hand corner is not showing up. When right clicking on the cell, I get the menu to add NEW notes or comments and can add a note which I can then go back and edit. However, the old notes I added some time ago can't be edited. I have tried the solution of resizing the column width as suggested by some but this does not work. Note that the worksheet is NOT protected. Any help would be appreciated.

SOLVED. I forget that the notations added last year were via the Data Validation comment and NOT by adding a note to the cell. Sorry about the "old age" memory that seems to be failing a bit.