Things that might be helpful to know (Agenda version, OS and model, etc): Latest version of Agenda. Syncing between iOS (on iPad and iPhone).
It’s not a major issue, just a little distracting. I have two or three notes that - whenever I delete unwanted text - it reappears. I’ve done my best to delete on both iPhone and iPad at about the same time. When I reopen the notes, the unwanted text is back.
There was an issue in 4.1.1 that caused this. Unfortunately it can carry over a bit into 4.1.2, in the sense that if you edited something in 4.1.1, and closed it, and now open it again in 4.1.2, you may see the resurrected text. If you delete it in 4.1.2 it should stay deleted.
My advice is to update all of your devices to 4.1.2. Let us know if you see an edit you made on 4.1.2 get resurrected, because that should certainly not happen.