disappointed.!!!

I took my car to Barloworld Toyota Tygervalley for a major service. Have done all my services there since I bought my car...nothing was wrong with it as far as I know.....when I got it back it overheated. ...on closer inspection. I found the radiator and reservoir empty. ....filled it up....found it without water again....on the same day...parked it overnight and found a pool of water under the car....again no water in radiator and reservoir. Took it back to Toyota and they found that the radiator had a big hole in it. I don't understand how they didn't pick up the hole on radiator during the major service. The hole wasn't there when I took it in and what upset me the most is that my car started to overheat. I ended up paying for a new radiator. Luckily it didn't blow a gasket, but the damage has been done. Toyota phoned and apologised, but...