Starting up my car

I have a 99 Buick Regal and if the car sits for long periods of time (more than about 6 hours) it won’t start immediately. When I turn the key the car sounds like it is going to start but it cuts right off. After about 4 or 5 attempts it eventually starts. I took it to a local meineke, left it overnight so they can try to start it and they had no clue as to why this is happening.

Let's get something straight.  When you turn the key and it is having its problem, does the starter turn over the engine but it just does not start or does the starter not turn over the engine, or maybe turns it over slowly or just click?

I have no idea.

Are you saying that, “While the engine is cranking, it suddenly cuts off”? And it will do this several times (cut off suddenly) before it will continue to crank and start the engine?