Storage problem

Hello.

My mother have a problem wich prevents her to play. When we want to play, this message appears : " You are almost out of data storage space ! Minecraft has restricted access to this feature until you clear up additionnal storage space. "

But there is still storage space, she have one world, and the switch have again a lot of storage space !

The last time when it happened to her, it's the update which erased the problem. I don't know what to do, I have tried all I could do.