@Feedback2016 - While I can't be 100% certain, I really don't believe this was ever a feature. I do know that we offer the ability to edit an invoice before it has been sent, but not afterward. 

@tomasguitarra - Would you mind sharing more details about the use-case? I'm not sure that I completely understand. It seems like it would be important for the customer to have the same copy of the invoice that you have on file. Thanks! 

One aspect of my work as a musician is teaching.  I am dealing with about 15 students.  I bill monthly based on 4-lesson cycles.  I include in the message session of each invoice the dates of the four previous lessons as well as the dates of the lesson cycle being billed in the current invoice.  Sometimes I make a mistake on these dates and I would like to go back and make the correction - since it is a record of exactly what the client is paying for.  However, such a correction really is for my internal use and not necessarily relevant for the client (unless they are very nitpicking - which not of them are).

Hey, @tomasguitarra — copy that. Thank you for taking the time to point this out. I'll be sure to surface your experience with this to our Product Liaison team. I would like to thank you for your patience as we're always working to make improvements based on seller feedback. Please keep in touch!