Adding a note to a chart
By default, notes are aligned in the first part of the chart object. When you add a note to a chart, you can set the note's position relative to the sides of the chart area or chart body. You can also use a report expression to position the note next to a data item within the chart. For example, in a bar chart showing revenue for each product line by country or region, you could type [Country or Region]='Canada' to position the note relative to the Canada bar.
Notes overwrite whatever is under them so you must position them properly.
If you apply more than one note, ensure that each note has a different position in the report so that they do not overwrite each other. You can also specify the order that they should be drawn in when the report runs. If you have two notes with the same coordinates, the first one in the list is drawn first and the next one is drawn before the first.