You should check your fallback to SMS settings. It could be that the time set for the fallback to SMS is too short after IP messages fail. For optimal use, SMS messages should be sent after 10-15 minutes if an IP message fails. Go to Settings > Preferences > Message Flow.
2. Why can’t I see all of the my messages in the app?
The app only displays messages from the past 30 days. This is true whether you install the app for the first time, or if you’ve delted the app and re-installed it.
3. There is a delay in receiving IP messages (push notifications) on my phone. How can I fix this?
Go to your phone’s settings and make sure Wi-Fi optimization is unchecked. For Android OS 4.4, Settings > Wi-Fi > Menu Button > Advanced > Wi-Fi optimization.