Windscreen chipped

I took my vehicle for a 30k service yesterday and went to take it at 4:30pm in the afternoon. I only noticed on my way back home that my windscreen has a chip. I went back today morning to complain to the manager and he refused to fix my car and said he is not taking responsibility. I have a copy of my car where it has dents and nothing was said about my windscreen being chipped and requiring repair. I am so angry and disappointed that they don't want to take responsibility on their fault.