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Parts for GE TBXY14SPGRWH - AppliancePartsPros.com

Sounds like the drain tube may be plugged so the water generated by the defrost cycle is dripping into the fresh food section.

Some units drain directly from thye pan under the evaporator coils in the freezer. Others drain into a funnel iat the top of the fresh food section and then out the back down to the drip tray. I cannot tell for sure which yours is from the parts breakdown but am leaning towards the latter.

Check that the drain tube is clear.
If plugged a turkey baster with warm water, an air compressor with low pressure or a wire can often be used to clear it.

Also check that it is not plugged with dust etc. at the drain pan end.
You might as well clean the condenser/compressor fan and the condenser coils while you are down there.

If it looks like stuff is growing in the tube I would flush it with a 10% bleach solution. This should kill the stuff and let you flush it out. You may have to do this several times, let it sit for 15 minutes or so between flushes.

Be careful that the drip tray does not overflow and empty the drip tray after you are done.

Be sure to unplug the unit while doing this.