Ill take an educated guess that it is a volumetric dose type commercial machine.
It sounds like your volume needs re-programming back to 30ml/60ml single/double. The programmed volume is dependant on grind, dose and tamp used in the basket. It would help if you could give us some more info about your machine.
In relation to the steaming, I mean absolutely no offence, but it sounds like you need more practice, but Ill defer to the pros in relation to steaming with a commercial machine.
Give us some more info, and Im sure that the answers will come forth.