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My name is Billy. Where is the air handler inside located? Attic, basement? And do you know where the water drain from the unit goes?
The reason I ask is the thermostat can lose power if the unit is in attic and has a water safety switch...do you have easy access to the attic to check something?
With the symptoms you describe the drain has gotten plugged that drains the condensate away..it shuts off thermostat to protect ceiling from water damage.
The drain must be cleared and operation will return. If you know where the end of the drain is garage..you can suck it out with a shop vacuum.
I wish you the best