How to fix my battery

@kundangupt29104 you really don't fix a battery. You replace it. Since iFixit does not yet have a specific guide for this, use something like this video Replacement videos are readily available at many online stores.

While you work on your phone, 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 issues with their device. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!