On Minecraft Pocket Edition Realms you can not set realms to peaceful mode.

Ok so every time i go on mine craft pe realms and i try setting it to peaceful mode, it fails. this is on all devices. Im the owner of realm and it doesn't work but even if people on the realm with peaceful mode on and it still doesn't work. I've even tried exiting realm and rejoining. it doesn't work even if I'm the only one on.