Laptop turns off by itself

Hello, i bought a dell xps13 laptop that is not touchscreen and i recieved yesterday, it seems to work fine until I unplug the charger and it works for about 5 minutes and it turns off by itself, keep in mind I've only had it for about a day and i haven't downloaded anything yet, but it is not gonna work for me because im going to have to always charge it while im using it but at school its really hard to find places to charge it, i really need help
thank you