Recovering deleted work

While duplicating a board and working on the duplicated board, I deleted a bunch of content and replaced it with content a copied in from another board. The deleted content has disappeared from the original board.
I tried ctrl Z, it didn’t work. Then I tried going through the activity, but it only included activity from the board that the copied content came from.
In trying to recover the deleted content I went back going back through versions and history, however the Board History only goes back to July 22. Today is July 31, meaning all work in that period has been lost. Please advise.