I was developing a program. Then after the incidence as explained in the description. Pls what caused that and how do i prevent

Question

was developing a program. Then after introduced a new page, i run the code using easy html app on my phone. Then a new page appeared. I went back to d code and discovered all my codes vanished.

Answer 1

Not sure about easy html and I don't used it anyway.
But certain bugs are common in apps where they have to run upon different situations and environment.
Just reinstall the app or change your device.
It may help if problems is in the app.