Incomplete work

On the 13th of the month I took in my car to this dealer for my normal annual service, booked in advance for a Saturday so I am not in convenience to anyone at work to drop off and collect my car; I arrived on time and the service was ever so pleasant (this is the only place I've ever serviced my car and the expectation has been set high). I was dropped off at gym but to my surprise was called literally 2 hours (if not less) later to say everything has been done, I figured its Saturday and there aren't a lot of cars; picked up the car and this is where I am very frustrated as i was told: -> there wasn't enough time so not everything was done -> i was told to bring back the car in to change both front and back break pads before end of June -> there is a warning light on my dash that went in which wasn't attended to and -> my windscreen wipers went changed.

Needless to say my car is almost for sure high risk as i drive in the rain, I can actually feel the car wobble as I break.

I was then called by a service person at Hatfield VW who asked me for a survey and I mentioned all this and he said he would take this up with the service manager at the branch; 3/4 days later I am yet to get any feedback. I was charged for the half service done, does this mean I would then have to pay again the following month for a half done job??

I am very disappointed as this has always been my number one even though I am located to another one like 5 minutes drive from the office, really really disappointed.