My vivo y19 keeps turning off and on and battery draining

@mithoonraj84670 there very first thing you want to do is to replace the battery. After that you need to determine what maybe using the battery power. Check all of your settings to ensure you are using a power saver setting. Again, start with a new battery. Use something like this video to replace the battery. If nothing else, it will provide a known-well starting point for further troubleshooting.

While you work on changing the battery, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has the same problem as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Automatic off when charged off