So I bought my Ninja 500 SE just yesterday brand new

So I bought my Ninja 500 SE just yesterday brand new, and when I was riding it back home I noticed the check engine light, actually I already saw this since the dealership and it hadn't crossed my mind that it was a problem. So I called up the Kawasaki dealership and they told me they left transport mode on because their computer was supposedly broken since January 6 and they will turn it off when I get my first PMS. They said it was nothing to worry about. It just felt so sketchy and I just wanted to ask for help on what this engine light actually means and advice on what to do next. I don't want to throw away the 3 year warranty I have on this bike and my mom wants the dealership to replace the whole bike if its anything serious. This is my very first bike and the first bike my family owns so we have no idea on what to do. It would be a great help if anyone knows what this light actually means and steps on how to handle the dealership. Thank you!