"Asleep at the switch" is an idiom that is commonly used to describe someone who is not paying attention or who is neglecting their responsibilities. The phrase originates from the railroad industry when switch operators, who were responsible for directing the movement of trains, would occasionally fall asleep on the job.
Some synonyms for "asleep at the switch" include "negligent", "inattentive", "unaware", "careless", "distracted", "indifferent", "reckless" and "sluggish". These words can be used to describe situations where someone is not fulfilling their obligations, showing a lack of concern or dedication, or simply being lazy. By using synonyms effectively, you can add variety to your writing or conversation while still effectively communicating your point.