Power button not working

Hi, I just bought Clara Color yesterday, I’ve set it up, it’s was working perfectly the whole day. When I was going to bed I wanted to put it to sleep mode (and myself too) but I couldn’t, the power button wasn’t working. I waited 5 min and it went to sleep automatically yet when I wanted to wake it up, again, I couldn’t. The only thing that worked was plugging it with charger (even though it still had over 50% so not a battery problem).

I still haven’t figured it out, please does anyone has any idea what happened or how to fix it? I used it for less than 24 hours…