What is the problem?????

[bashar]

I have Iphone 5s and my problem is (when the screen of my phone is lock and someone call me in "viber application only" I move the slide to answer, but I hear the viber ringing is continuously and it cut after little time).
But this problem is not happened when the screen of my phone was not lock, just press on "answer button " and answer

This problem just when the screen is lock

 

[alex2020]

I have Iphone 5s and my problem is (when the screen of my phone is lock and someone call me in "viber application only" I move the slide to answer, but I hear the viber ringing is continuously and it cut after little time).
But this problem is not happened when the screen of my phone was not lock, just press on "answer button " and answer

This problem just when the screen is lock

Have you tried deleting the application and installing it again? Tiresome, I know but it works most of the time.