Isit possible when my player up level and their health can get more longer?

As title..i m using level plugin..isit possible when my player level up and their healh will become more longer using this code?my server using php5..last time i use this code when level up..my player will die..so i want try to recode the plugin..and i dont know where the plugin go wrong..

What doesn't work?

It was a level plugin..and i want my players can get extra 1 health bar after they level up..
Example : now original mcpe health bar have 10 ♡ ,after my players level up..their healh bar will increase 1..thats mean have 11 ♡..
Problem is when player up level..they will die..and health bar still the same..no increase ♡ ..

That's a Pocketmine bug, not a bug of your Plugin.

Okk thankss..i will wait for pocketmine update ^^