Volume button not working

@pranav55998 could most certainly be a bad volume button flex. To replace this and since iFixit does not yet have a guide for that, use the one from here It is written in Spanish so use a browser that does the translating for you, if needed. The volume button flex is 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 a device with the same issues as you do. 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!