Mike, I must apologize for my ignorance of these things, but I tend to write things out long-hand. Not knowing the meaning of "n/m" I Googled and found these:

N/M Nevermind

N/M No Message

N/M Not Meaningful

N/M Nuthin' Much

But since all four of those meanings are not the same, what meaning applies to your use of "n/m"?

Thanks.