So I just opened my Ubuntu in VM virtual box after a while in my Windows 10 PC.It booted normally but when I place the cursor over the screen(in ubuntu OS) the screen starts to glitch.I don't know why it is happening since its the first time it ever has happened.
One more thing, when it first loads HOMEPAGE, the cursor is a gray box instead of the mouse pointer.
I tried to restart the VM Virtual Box but no change, the screen still flickers