Iphone X Problem Help please.

i Bought a Iphone X "64 gb" on Nov 3rd and everything was perfect i backed up my date and all good after 1 week ! i went to bed to get some sleep so i connected my phone to the charger beside me and i fall asleep and when i woke up i looked at my phone it was shown the apple logo with black screen it's frozen nothing i can do to solve the problem so i went to apple website and i followed the instruction i hard rest my phone and still didn't work so i hard rest it so i can update or restore my software by using itunes and the update didn't work so i had to restore my phone and this one worked and the phone was back On like new but i lost so many new date 😟and numbers i got in the last 2 weeks ! so my question is why did that happen to my phone ? it's a new brand phone i paid in full why did that happen to it? i was so upset it never happened to any of my iPhone before i had 5s and 6s now X happend to it 😟yeah one more thing before i went to bed there was a new update for the software launched by apple it was 11.1.1 i updated it and the phone was turned on again everything was okay then i went to bed so i dont think that was the problem please help me tell me why did that happen to it !?