When I try to play minecraft pe addition, it wont let me get any blocks or move in different directions. I can't place any blocks either

When I try to play Minecraft, I can't move around or pick up blocks place them, or go forward, backwards, side - side. I can't fly or dig anything. This is happening in all of my worlds not just one. This has been happening for three months now. And I've tried looking in the settings, nothing has worked. And I have put in effort to trying to fix it. So I don't want to delete this app. Please help and thank you.