Rear Glass

Hi there,
Yesterday, my razer phone 2 felt on the groud, the rear glass is now broken :(
I bought my phone the 26 December 2018, what should i do?
Beeing relatively unaware of garanties and all this stuff, i ask you, dear forumers
(i've also contacted support, but in France no direct web chat or no call to after sale service (very sad) so i'm waiting for them to answer my mail)
I didn't find nowhere to buy a new rear glass (i can change it on my own if necessary, i've done it a few time on old sony Z5 cellphones) Do you know where i can find a new one? I live in france
I don't trust repairmen in malls or in store who takes about 50 euros to excanche mine with a poor quality glass that i can buy 10 euros