Is it still on iTunes? If so, re-add it to the phone from there. Otherwise, it's just a Smart Playlist that can be manually (re)created. The settings are:
First column: Second column : Third column
Date Added : is in the last : x : Weeks/Days/whatever
Media Kind: Is : Music
Tick the box for "live updating".
Thank you my friend but the instructions are a bit confusing to me.
What do you mean by....First column: Second column : Third column?
I totally confused....