please help

My problem is the parents are overshadowing me like crazy. Every week telling me the same thing! I am tired of it, it makes me morning stressful. I could 100% understand if I was doing something wrong or could do something better. But I haven't done anything wrong what's so ever all I do is for the little girls comfort and her getting to school on time. I am thinking about just stop taking her to school because I'm tired of hearing the same redundant information over and over again Even after I give reassurance that   all is well! Worse part I've been babysitting this child for 7 years and we are relatives. I'm just beyond annoyed because I ask myself daily 'what can I do to improve her travel experience daily?' 

Everything I do is time efficient and I do nothing wrong. I'm just getting yelled at and I'm annoyed with it. I'm damn good at what I do. Thing is the parents don't advise me or suggest this. they yell at me, as if I am doing the worse job ever. I am a wonderful babysitter, I take everything I do seriously and I'm always finding ways to improve myself, and I am punctual. I truly do not see the problem. I don't need to be treated like a child and told what to do, I have a mind and I can think for myself. I am tired of being yelled at for doing everything I am supposed to be doing. if this was my boss I would completely understand but even then I would be excelling in my work. I love feedback and constructive criticism but when I am told to do the same thing over and over again and I've already been doing that stuff! I do not like it and want it to stop.

My future career is programming, so I have a lot of patience and I'm use to improving and problem solving but this is just mentally 

what should I do? 

P.S:: I apologize for ill grammar. I'm using my phone and I have to go back and babysit. Typing this as quickly as possible. 

Edit: I quit. I Believe in myself and know that I will be fine. 

Thank you for all your answers.