Your clock is running slow or fast.
If the clock has a pendulum, look for a nut either under the pendulum bob (round thing at the end) or inside the bob. If there is one, tightening that nut to raise the bob will make the clock go faster, and loosening that nut to lower the bob will make it go slower. If your clock is off just a few minutes, use small (1/2 turn) increments, then observe it for a while.
If your bob has no adjustment, of if your clock has a balance wheel instead of a pendulum, look for another adjusting mechanism. Chances are it's labeled with +/- or F/S or R/A. If your clock is running slow, turn the adjusting device toward + or F or A. If your clock is running fast, turn the adjuster toward - or S or R.
Prestige Clock Repair
Bluff Heights (near 4th and Junipero)
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