Disappointed by a brand I trusted

I am not happy at all I took my car for service. I got a quote and took it the following day. On the quote it clearly states they will change my brake fluid i get my car later that day my battery is dead that's not a problem the brake fluid is still the same. My car is a Toyota tazz 1.3 2006 model the service kit costs about 400.I took it Toyota thinking am going to get the best service what it i pay for? I call and told to bring the car back the following day. I took it no explanation I am told an investigation will take place. Is it because am a woman or what is the reason behind all this?