Hello all I'm new here so now that I've said hi lets get to it

I went out today to run some errands and she wouldnt start right up like normal, she's sounding like she normally does when I start the engine but it wont turn over, I tried a few things to get it started and finally whatb has worked multiple times in between the different errands is I have to turn the key to the on position then off multiple times average was about 8ish, my fiancee drove it yesterday with no problems whatsoever, the only problems I have had in it prior to this was a small transmission issue and a misfire on three due to a emissions leak that I have yet to track down any help on this would be great