My Minecraft world is not loading it is telling me, Minecraft is unable to save your progress

Please fix this bug l am not able to play minecraft

This is not a bug read what it says, you need to clear up storage on your device. 

copy of MCPE-137345

My storage is 80% left 

Im guessing that isn't enough or you just don't have a lot of storage installed.

My world is only 250 mb 

I have so much in my device , I am also able to make a new world but I am not able play in that world ,I don't know why

how much storage is left in your device give the amount not the %

32 gb left

Please stop duplicating your own report (MCPE-137248).