DEAR MISS MANNERS: Five years ago, I left a company where I was a supervisor for several years. I still receive calls (actually, text messages) from former employees every once in a while, requesting letters of recommendation or asking if they can put me down as a reference for a job they are applying for. Usually, I say yes, as I know it can be difficult finding a job and wanting to move on to a better position. Last year, I ran into a co-worker from my old company at a meeting we were attending. She asked if I could be a reference for her. I said yes. Earlier this year, I got another text fr…