Nipu_1998 , via OnePlus 9 Pro , Jul 21, 2021 : Hi, After the latest google messages update, many of the OnePlus 9 series users are reporting that the system gives battery drain warning for the messages app. The issue was a result of the battery consumption optimisation of the messages app in the latest update. Here's how to fix it : 1. Open settings 2. Go to apps and notification settings 3. Select the messages app from the app list 4. Click on the three dot menu in the upper right corner 5. Click on un-install all updates. Make sure to turn off the auto update feature in the playstore too.