Most pendulum clocks stop running if they have been moved or if the wooden case warps a little. They need to be run in an upright postition. Try shimming the base with progressive strips of thin material such as paper or plastic, or even old veneer strips. Set the pendulum swinging gently and listen to the beat of the tick. It should be regular and steady. It is misses try lifting one side of the clock. If that fails, try lifting the other side. You can also bend the "crutch" a little but that is best left to a pro. Good luck.
George, August 2009
Take it back to the repair person. If they did not give you a one year guarantee, take it to someone that will. Every clock repair should have a one year guarantee.