Split screen second player not working

Second player split screen loads in, hunger doesn't go down, can mine but blocks don't go into invent but items from killed mobs do. When anything is mined say wheat and seeds are placed there the wheat just gets planted. If sand is mined & cobblestone placed the sand appears on place on bottom screen but shows as it should be on the top. All permissions are granted and was working fine then just stopped, happens on all worlds & in creative too.