So far- have you found any particular methods to be the most effective? (Return postage envelopes with a form letter, online tools, other options)

My grandma, who passed a bit less than two years ago is still receiving all sorts of junk mail. I have tried unsubscribing normal ways from some of it (online forms, etc) and none of that seems to work at all.

I do use the "do not mail" junk mail opt-outs which has reduced the volume that comes in both her name and mine, but there's still loads of "previously accepted/subscribed-to mail" that I can't seem to put a stop to- even if I use the publisher/sender's preferred opt-out method.