Make sure that your data is backed up using Android Data Extraction as the below steps may result in loss of data. Firstly, power off the device holding the volume button up, home button and power button at the same time. When you feel the phone vibrate, release the power button till you see Android System Recovery appear on your screen.
Find it and tap on it to continue. Next, scroll to the bottom of the Messages Settings page and tap on Repeat Alerts. This page of Messages Notifications Settings controls how many times your iPhone will repeat the alert notification when you receive a new SMS or iMessage while the phone is locked. As mentioned earlier, each alert will arrive ...