Voip delegate "didReceiveIncomingPushWithPayload" not called when app is in killed and device locked.

I am working in VOIP application. I can receive voip push when app in background or foreground. But when an app is killed and device locked voip delegate "didReceiveIncomingPushWithPayload" method not called.

Also, I am facing below crash

Killing VoIP app <private> because it failed to post an incoming call in time

VoIP push for app <private> dropped on the floor

Voip delegate "didReceiveIncomingPushWithPayload" not called when app is in killed and device locked.
 
 
Q