Help screen blacks out when calling

[njbw]

I have a problem when making calls, as soon as the call is connected the screen goes blank. When I finish the call I cant get the screen back on, the phone does not respond, because any buttons are working. I have to pull the battery out in order to hang up. I think the proximity sensor does not realize that i m not calling anymore. (I m not using any kind of screen protector)
What can I do?
Thanks for your help!

 

[GX390]

Keep putting your hand on the proximity sensor and taking it away until the screen comes back on

 

[njbw]

thanks, but there must be a better solution
(it doesnt make any difference if I keep putting my finger on the proximity sensor,it already "thinks" that i m still touching it with my face, thats why it keeps the blank screen modus)

 

[ElasticNinja]

what ROM are you using?