[IOS] Not receiving calls if App is not opened for few days

### Issue Summary

If my IOS app is in terminated state for a few days (3-4 days) then it just stops receiving phone call. In twilio console I can see that an attempt was made to call on my client but there's no ring. Its like the second the call is made from twilio to my client, the very next second the call ends with "no-answer" status and twilio console shows no error logs. But If I open my app, logout or login and then try, then it works perfectly fine.

### Steps to Reproduce

1. Keep the app in terminated state for few days then try calling