BP BUG

I add something to the files I created with Unreal engine, I say save, it saves when the application is open, but when I close and open the application, everything I do is deleted, can anyone help me what is the cause of this problem?

What do you mean you “add” something? As in a new node? Or are you migrating new BPs?

i got it done thank you for the answering

Yeah no problem, good luck with your project