LG Vortex freezing issue

[FinalBlade7]

Whenever I call someone or they call me my LG Vortex screen goes blank. I can still talk to the other person but when they hang up (there isn't a way that I can) the screen is black. I can't press any buttons that will make it go to the lock screen it just stays black. The first few times this happened i just took out the battery. Now even that doesn't always work. I had to hold down the lock and down volume button. Please help this is getting really annoying.

 

[dfgged]

I don't have this phone, but have you tried a factory reset?

 

[FinalBlade7]

Yes I have. And I have to re-activate it. But it still does the exact same thing. I can't activate because the screen stays black.