What is my next step?

Ok so my neighbor is not taking care of their yard, so I wrote them a note. I was not rude but I did not put who it was from. Then the mailman told them it was me, he knew it was me who worte it. Now I do not want a fued and I did nto tell them in person beacuse I dont know them. Now I feel like an *** becaus ethey know it was me. What do I do?