text message tone plays when im in a phone call

[Unregistered]

Hi everyone I'm new here, I have an issue in windows phone 8.1 on a Lumia 520 at&t service. When I'm a phone call I'll get a Text and I hear the text tone playing in the phone interrupting the phone call. Is there anyway to turn text notification sound off when I'm in a phone call. Wanna leave my text tone on just dont want it to go off when I'm in a phone call
thanks everyone