Please make sure that the clock is adjusted properly on the wall. The clock must be placed in a correct vertical position so that the pendulum can swing freely.
It is suggested to “listen” to the clock and be sure that the clock has an even Tick-Tock sound. Do not adjust the clock with your eyes, do it with your ears. This is adjusted by moving the clock to the right or left, until you hear the tick tock sound which is even.