You can easily copy your existing notes from one layer to another within a few clicks. The title and description will remain the same in the copied note. However, the comments on the original note won't be copied along with it. Please follow the below steps to duplicate a note.
Click on the note that you want to clone
Click on the three dots as shown in the video below and select the second last option, Copy to Another View
Click the down arrow icon to expand the dropdown menu and choose the layer you want to clone your note.
Click the Copy button