How to get someone to ask for pick-up/print a manifest

Hello so I just want to some advice on how to make a customer understand something. So recently a house on my route has massively increased the amount of stuff they want me to pick up. To the point it now.blocks both their door and mailbox and most like a fourth of their porch. It not every day or even every week but when it does happen it takes me so long to load it all in or I have to finish my route then go back. I tried leaving a note in their mailbox asking if they can at least print me the manifest or what every so I can just scan that instead of doing it one by one. That was like 2 weeks ago and right now they are shipping stuff out like twice a week or none at all.

So does anyone have any advice on how to talk with this customer as they are never home when I come.by and I don't think they notice or anything my note.