Dear second floor, the coat is washed and hanging back on your door

It was minus eight in Praga and I had arrived from a warm country with one thin jacket. On the third morning there was a thick wool coat hanging on my door handle with a small note that said, from the second floor. I still do not know who it was. I wore it all winter. On the first warm day I washed it and hung it back on the second floor door, with a note of my own. The note said, thank you. It did not say anything else. I did not know what to add.