Brakes go to floor Acura dealer said vsa modulator has air that can not be bled on 2007 Acura MDX

Already replaced master cylinder brakes fine for about a month took car to dealer they bled the brake line using a computer again brakes fine for a month replace modulator 1000 miles on car 81000

Asked by for the 2007 Acura MDX
If there is air in the system they should be able to get it out unless there is a seal or line opening letting it back in.That is the only way it can happen.With the HDS and a drain twin brake bleeder.(both of which we have)you should be able to bleed it if there is no leaks.
Thanks I was told that the air was in the modulator. What is HDS? And what is the cost for your service
HDS is the Honda diagnostic system.Acura included.We charge our diagnostic time by the hour.$100.00 per hr.It should be a 1-2 hr job to do that service.
Thank you will see you soon