I hope the guy who cleaned the throttle body didn't damage any of the sensors attached to it or either the sensors are not cleaned properly... since this kind of issue is more evident in the cars running on CNG and they need to get throttle body and sensors cleaned up with some cleaning agent like WD-40 or petrol ...
Once i have the same problem with my civic which was on CNG but after throttle body cleaning the problem was solved....
Just check the sensors....