Minute Hand stops at 7 minutes to the Hour

by Dwight
(Williambyrg , VA)

My antique German pendulum wall clock works fine all the time as does the minute hand except each time it gets to about 7 minutes to the hour, it stops though the pendulum keeps going.

If I advance manually the minute hand it them moves very well for the next hour until it returns to the same spot where the minute hand again fails to advance again. What is my problem?

Thanks- Dwight