Adding Comments to a Pivot Chart that changes when data changes

Hi everyone

Would like to check if there is anyway to add comments to a Pivot chart.

I have a chart linked to a pivot table that shows Qty of product sold by months with multiple products in it.

So Product A can be chosen to see the qty sold by month or Product B can be chosen

However, I would like to add comments to it for example: Product A - Dec 2021 - High qty sold due to increased marketing budget

Any idea of how I can keep track of it and how do I do it and where do I key in the comments as the comments won't appear in the pivot table.

Thanks in advance.