Key fragments not dropping ?

so today i've played exactly 7 normal matches with 4 premade friends and won 5 out of those 7 and didn't drop a single fragment :( same for some of my friends they don't seem to drop any after getting the first 3 / 5 fragments and the thing is i'm on EUW so everyone got their 4 chests but no fragments and this will reset on 1st of april which means we'll have some unused chests in our hextech inventory and i'm pretty sure even NA players didn't drop that much fragments either...