This question already has an answer here:

I have dual boot in my PC with Windows 10 and Ubuntu 16.04. A windows partition of 500 GB NTFS formatted disappeared and now showing in Ubuntu with ext4 format. I was trying to mount that partition into Ubuntu. Now partition is missing in windows but showing in ubuntu. But the partition is completely empty. I had important data in it. How do I recover that data?

marked as duplicate by Rinzwind, karel, Andrea Lazzarotto, waltinator, Kevin Bowen Jun 27 '18 at 21:02

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.