I've hit lvl 200 on PBE for quite some time, and from that point on, I haven't received a single level up reward. No capsules of any kind, no BE, nothing. My only source of BE is hextech chests earned by getting S- or higher on a champion (which is limited to 1 per champ, and 4 per week), and purchasing chests with RP (which have been discontinued) and opening them. It doesn't seem like many other people have this issue which is even more weird, so it might be linked to level 200. I'm currently level 226, and I've run 26 levels (maybe more) without a single reward.