Playlist Arrangement......

Yesterday morning the songs in my playlist(s) were able to be moved around in the playlist by clicking on the song and dragging it to the order you wanted in on/in the playlist. Yesterday evening, I purchased two new songs, added them to my playlist, and when I went to 'click-n-drag' them into place, they wouldn't move - in fact, none of the songs now move.

I find that my playlist seems to be in alphabetical order now, I can not click-n-drag songs to move them around in the order I would like them. What do I need to do to change this back so that I am able to arrange my songs in a playlist? What did I do to change this?

Help........ Thank you.