Why am I unable to send an edit request for an existing memorial?
Because we don't do it that way in BillionGraves. If you need to make editing changes to a record (not a memorial) you can do it yourself. If you are a real beginner and not sure what to do, you can copy the URL and send it with a very specific message to Support to ask for help doing it.
this is a completely user-based data entry and editing web site, but once the data are entered for an image or record, it goes public and then anyone with membership can edit that record's' data.
If this does not anwer your question, please reply here with more specific details. We can't answer if we don't know the question.