Small Engines (Lawn Mowers, etc.): Lawnmower stuck, briggs stratton, wont move

Question
Hello,
 I have a lawn mower that when you start it and mow you have to hold the lever down with your hands, pull the cord then mow.  But for some reason when i hold the handle down with my left hand and pull the cord with my right hand the cord wont move?
Is it anything I can do to fix it?
The lawn mower is a briggs&stratton 120000 series
Thanks
Laura

Answer
It is likely just needs an adjustment to the blade brake cable to make sure the brake disengages when the handle is down.  If the cable is broken or an adjustment doesn't correct the problem, the problem may be with the blade brake assembly.  Hope this helps.