If it like a breaker, they sometimes get worn and 'lazy', and will trip over for no reason mainly due to old age and overuse as an on/off switch.
Or the cooler is drawing too much current (amps) for some reason.
Or water is mixing with electricity.
An electrician or HVAC tech can advise.
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You need to check the sensor or float switch for the water storage tank. It is either stuck or has failed and it's locking the unit out. It does this so the tank doesn't run over and flood the floor.