I don't remember having to restart JTAlert when I have changed that setting. At the bottom of the screen, just below Mike's scree shot above, there are 3 buttons. The right hand one is something like Save or Apply  (I'm on the wrong device now. No JTA for android). Hit that and then the left hand one.
John KA5BJC
On the laptop now and the buttons to hit are Save, then OK
John