I could not find any information so far about why it would have 2 dates, though I could speculate. One says S-61-MO (or MD) and the other says F-62-JC. It has the long number/letter series that includes the model (H625) and 2 smaller groups of numbers in different locations. I have a Harmony acoustic guitar branded as a Silvertone that apparently has 2 different dates stamped on the inside back of the guitar (visible through the sound hole). Your guitar needs an electronics evaluation and cleaning.Don't replace any vintage components unless you absolutely have to.This can be a variety of things from dead capacitors, dirty potentiometers, shorted wires, and even dead pickups.There is no sound coming from the electronics.Your guitar needs a bridge reglue and often a bridge plate patch.The only fix is to remove the bridge, prep the area, sand the bridge to match, and reglue it. Do not use glue to fill the gaps or drive screws into the bridge to bring it back down.Many bridges are glued directly onto the lacquer which causes them to lift and raise the action.As string tension and climate shift the wood in a guitar, they inevitably need the neck to be steamed off and a new angle carved relative to the body.The strings are too high off the fretboard.Your guitar needs a fretboard planing and refret or more ideally a truss rod installation.

Most Harmony guitars lack adjustable truss rods (or rods that still work) and so forward bow cannot be easily repaired.

The strings are buzzy or the neck is bowed.

Frets are like tires on your car, they need replacing after being used a lot.

Do not shove glue in there or drive a screw through the heel.

The neck heel is pulling away from the body.

Your guitar needs proper humidity and cleats.

Do not try to fill the cracks with glue or put clamps on the guitar to press it together.

This occurs when an instrument is exposed to a climate different than the ideal (70 degrees Fahrenheit and 45-50% humidity) and the wood has shrunk.

Old silvertone guitars