Voice is not listen?

@ummeechauhan it is possible that this is a bad mic. It is solder on the charging board.

Use something like this video to work on your phone.

The M30s comes in different variations. SM-M307FN/DS (Global); SM-M307F/DS (India) make sure you get the right part for your specific model.

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 problem as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.