Suzuki Alto VXR brake issue

Hi,

I have a Suzuki Alto VXR 2007 model. In the last 5 years, at least four times the brakes on this car have failed. I take it to the Suzuki dealer and he fixes the issue for the issue to come back again.
Last time when the brake failed, I was told the booster has the problem and it is not pumping the brake fluid to the brakes. So it was replaced. The brakes are still very light and sometime pedal need to be pressed 3/4 times quickly to apply brakes. Please advise what should I do? If I change the whole brake booster assembly with a brand new one, will it help?

Please help.

I didn't find the right solution from the Internet.

References:-



Thanks!