ringer won't switch to vibrate-only mode

[newiphoneuser2013]

I always keep the ringer volume all the way down to the vibrate setting on my 5s.  Not sure how it happened, but at some point my phone switched out of vibrate mode and now when I use the volume buttons on the side of my phone the volume will go up and down but it won't allow me to go all the way down to vibrate only mode.  I didn't change anything in my settings that I'm aware of.  I have it on the lowest volume right now, but I want to get it back to vibrate only.  Tried restarting the phone and it didn't change anything.  Any suggestions

[#2 · Accepted solution]

Upper left top, slide switch to have it just vibrate.

Good Luck